Nauki Techniczne

Archives of Civil Engineering

Zawartość

Archives of Civil Engineering | 2024 | vol. 70 | No 3

Abstrakt

When testing soil parameters, the measured parameter values are only approximations of the true values. The measurand is determined based on metrological uncertainties or using statistical models for analysing data. Some parameters of the soil state present strong correlations, but others do not always provide simple correspondences. Multiple correlations between geotechnical parameters can provide a new perspective regarding the mutual relations between these parameters and may improve the fit of different soil parameters in geotechnical design procedures. Statistical modelling based on observed data generally involves a comparison between theoretical expectancies and practical surveys. Multidimensional regression models are useful for revealing the influences of several independent variables on one dependent variable. Statistical parameters and a quantitative approach can be used to define the relationships between several factors. Presented results claim that triple depended correlations may bring some corrects in relationships of soil parameters as against to double depended correlations. The differences in coefficients of determination are significant. Three variables involved stronger correlations.
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Autorzy i Afiliacje

Eligiusz Mieloszyk
1
ORCID: ORCID
Mariusz Wyroslak
2

  1. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, ul.Narutowicza 11/12, 80-233 Gdansk, Poland
  2. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, ul. Narutowicza11/12, 80-233 Gdansk, Poland

Abstrakt

Through the real-time monitoring of the internal force, alignment and suspender force in the process of bridge jacking construction, the measured data and theoretical calculation values obtained from the monitoring are compared and analyzed, and it is found that the measured data are in good agreement with the theoretical calculation values. The results show that through the analysis of the real-time monitoring data of the jacking process of the bridge, the measured stress values of the main beam are within the range of –40.79 MPa ~25.13 MPa, and the measured stress of the main arch is within –40.33 MPa ~16.06 MPa, which does not exceed the allowable stress range of the steel in the jacking process, and the structure is safe. The measured elevation of the line is in good agreement with the theoretical elevation, and the deviation is mostly less than 5 mm, and the maximum deviation does not exceed the limit value of 8mm. The difference between the measured cable force and the designed cable force in the stage of removing the temporary pier is very small, which does not exceed ±5% and meets the requirements of the specification. The research in this paper can provide a reference for the jacking construction of similar bridges.
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Autorzy i Afiliacje

Xilong Zheng
1
ORCID: ORCID
Di Guan
1
ORCID: ORCID

  1. Harbin University, School of Civil and Architectural Engineering, No.109 Zhongxing Da Dao, Harbin, China

Abstrakt

The SHM (Structural Health Monitoring) system deployed for an external prestressing tendon and steel plates rehabilitated continuous rigid frame bridge is introduced in this paper. Damages and deterioration of the large box girder was described as well as the rehabilitation plan. Data that were collected for 6 monthes were analyzed. Performance of the rehabilitated bridge, pattern of the collected data as well as investigation of the correlation between different types of data were the research focus. Temperature was considered as a major issue in the monitored data, the effort has been made to eliminate the effect of temperature in deformation and strain data. The best outlier detection method for deformation data is determined to be IQR analysis, for strain data a thresholding method of the empirical value 200 με was used, and lastly for tension force a thresholding method of 85% tension force was determined to be the best and most reasonable for outlier removal. The variation range of deflection and strain can help determine whether the vehicle load is over the limit.
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Autorzy i Afiliacje

Xilong Zheng
1
ORCID: ORCID

  1. Harbin University, School of Civil and Architectural Engineering, No.109 Zhongxing Da Dao, Harbin, China

Abstrakt

Taking real-time and effective preventive maintenance measures on in-service roads can reduce traffic congestion, eliminate potential road safety hazards, and greatly reduce road maintenance costs. Therefore, based on the Persson friction theory, this study first determines the evaluation indicators for the anti slip ability of asphalt pavement. And based on vehicle dynamics and contact friction between tires and road surface, the anti-skid thresholds of road surfaces for different road conditions and vehicle models are solved through simulation. This study utilizes Python and neural network algorithms to establish a decision-making model for anti-slip recovery technology of asphalt pavement. The experiment shows that the model trained by Back Propagation neural network has high accuracy. The training accuracy of the model is stable at around 0.90, and the training loss value is around 0.34, which can be used for decision-making in anti slip recovery technology. When the speed is less than 60 km/h, the increase in the threshold of dynamic friction coefficient is significant. The maximum difference in growth rate is 47.9%. When the speed exceeds 60 km/h, the increase in the threshold of dynamic friction coefficient gradually slows down. Therefore, at lower speeds, it is more essential to consider the variable value of the dynamic friction coefficient. When the speed is high, more consideration needs to be given to its reference value. This study provides a scientific basis for ensuring that the anti slip ability of the road surface always meets the requirements of driving safety, and has important engineering practical value, economic and social benefits.
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Autorzy i Afiliacje

Rui Cheng
1
ORCID: ORCID
Xinkai Li
2
ORCID: ORCID
Lichao Wang
3
ORCID: ORCID

  1. Heilongjiang Transportation Planning and Design Research Institute Group Co., Ltd., Harbin 150090, China
  2. School of Transportation Science and Engineering, Harbin Institute of Technology, Harbin 150090, China
  3. Heilongjiang Jiaotou Highway Construction Investment Co., Ltd., Harbin 150090, China,

Abstrakt

The paper deals with the phenomenon of post-breakage capacity in point-fixed laminated glass elements. It reports the results of an ongoing research project aimed at developing a reinforced point-fixed laminated glass element with locally embedded steel mesh. In total, 36 specimens (300 x 300 mm2º varying in the thickness of component panes (8, 10 and 12 mm) and the diameter of the reinforcing inserts (75, 110 and 150 mm) were tested. The specimens comprised two toughened glass panes, an EVA Clear interlayer and a woven steel mesh consisting of wires (0.35 mm in diameter) at a spacing of 1 x 1 mm2. The tests were carried out in a spatial testing machine allowing the point connector to be loaded at an angle of 45 degrees. This way of loading the fastener corresponds to its loading condition in an actual application (e.g. a glass canopy with diagonal rods). All samples presented similar behaviour during testing. In the first phase, the relationship between the load and the displacement refers to the elastic response of the sample to the load. Following the glass failure, there is a sudden drop in the force due to the loss of tensile stiffness of fractured glass. After this stage, progressive degradation of the samples occurs due to further loading. In this phase, the force is initially increasing and stabilising – this point is considered an ultimate failure (in the post-breakage phase), and the experiment is terminated. For all test series, the reinforcement increases the post-breakage capacity.
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Autorzy i Afiliacje

Marcin Kozłowski
1
Dominik Wasik
2
Maciej Cwyl
3
ORCID: ORCID

  1. Silesian University of Technology, Faculty of Civil Engineering, Akademicka 5, 44-100 Gliwice,Poland,
  2. Silesian University of Technology, Faculty of Civil Engineering, Akademicka 5, 44-100 Gliwice, Poland
  3. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw,Poland

Abstrakt

The paper presents results of experimental research involving assessment of the impact of temperature, fire exposure time, and the applied cooling method on the residual load-bearing capacity of high-strength construction steel bolts quenched and tempered (QT) in the production process, and their behavior under loading. The tests consisted in subjecting the bolts to simulated thermal impacts reflecting the environmental conditions of a real fire. During the experiment, a series of static tensile and shear tests were carried out on M20-8.8 construction bolts, exposed to the temperature of 100°C, 150°C, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C, 800°C, 900°C, and 1000°C for the periods of 300, 600, 1200, and 2400, respectively. Moreover, the research took into account different cooling methods and analyzed their impact. After heating, the first batch of bolts was cooled in air, by allowing them to cool freely in ambient temperature conditions. In the case of the second batch, the bolts were cooled down rapidly by immersion in water, thus simulating the effect of a rescue and firefighting operation. In each series – for statistical reasons – 3 samples were tested in order to verify correctness and repeatability of the results obtained. Residual values of the post-fire tensile strength and the post-fire shear strength were determined. Values of reduction coefficients of the residual post-fire load-bearing capacity were determined as the ratio of the current load-bearing capacity of the bolt subjected to the conditions corresponding to a relevant fire situation to its reference load-bearing capacity in the initial condition. In addition, the article discusses changes in the plasticity and behavior of bolts subjected to the described environmental impacts and points out to the observed failure mechanisms. Attention was drawn to causes of the observed phenomena, the sources of which should be sought in microstructural changes of the bolt material that occur in the process of heating and cooling, depending on the temperature reached during the simulated fire exposure.
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Autorzy i Afiliacje

Paweł A. Król
1
ORCID: ORCID

  1. University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland

Abstrakt

Experimental tests and numerical analyses were carried out on short, thin-walled channel columns with modified cross-sectional shape. The columns were loaded with an axial compressive force applied at the center of gravity of the cross section. Tests were carried out on a universal testing machine, while numerical analyses were performed in ANSYS software. The purpose of the tests was to determine the values of critical forces for the compressed columns and to determine the values of maximum forces at which failure of the columns occurs. Critical forces were determined based on the strain-averaged method. Based on the study, it was found that the strength and resistance to loss of stability of columns is primarily affected by their stiffness, and therefore by the shape of the cross-sections. In addition, for short columns, it seems more important to determine the value of maximum forces than the values of critical forces.
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Autorzy i Afiliacje

Aleksandra Magdalena Pawlak
1
ORCID: ORCID
Piotr Paczos
1
ORCID: ORCID

  1. Poznan University of Technology, Faculty of Mechanical Engineering, 3 Piotrowo Street, 60-965 Poznan, Poland

Abstrakt

The Eurocode 3-1-3 [1] provisions, according to which the rotational restraint of a cold-formed Z-purlin given by the sheeting has to be determined, set out guidelines for the first-generation trapezoidal sheets only in strictly defined cases, and for the second-generation sheets there are no guidelines at all. In the experimental tests presented in this paper, values of stiffness CD were determined in the case where trapezoidal sheeting with additional stiffening ribs in the middle of each trough was used. Then, the obtained values were confirmed by numerical simulations. The cases when fasteners are located in each trough next to the intermediate stiffener (the 1+1 arrangement) or near the trapezoidal sheeting webs in every second trough (the 2+0 arrangement) were analyzed. Values of stiffness CD obtained from the experiments were also compared with CD values obtained on the basis of the Eurocode 3-1-3 provisions. As a result of the analyses carried out, several changes to the Eurocode 3-1-3 provisions were proposed. Values of the rotational coefficient C100 for cases not covered by Eurocode 3-1-3 were presented and, in addition, a modification of this coefficient for the 1+1 fastener arrangement under gravity loading was proposed.
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Autorzy i Afiliacje

Michał Gajdzicki
1

  1. Lodz University of Technology, Faculty of Civil Engineering, Architecture and Environmental Engineering, Al. Politechniki 6, 93-590 Lodz, Poland,

Abstrakt

AECO is struggling with data loss, inefficient processes and low productivity in asset management. The remedy to these problems seems to be the idea of Digital Twin (DT). However, the frameworks proposed so far do not always support a solution to these problems. This paper conducts an extensive literature review to develop a conceptual framework for the Operation and Maintenance (O&M) phase for building facilities. The conceptual framework takes into account the increasingly popular Internet of Things (IoT) and Artificial Intelligence (AI) technologies. The foundation, however, is Building Information Modeling (BIM) technology. The presented framework, after appropriate modifications, can also be applied to infrastructure facilities or city fragments. The paper presents limitations and directions for further research. The DT paradigm has been adopted and its adoption is ongoing. Its implementation will progress in the coming years. The advantages and benefits are certainly more numerous than the barriers and risks posed by the use of DT.
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Autorzy i Afiliacje

Andrzej Szymon Borkowski
1

  1. Warsaw University of Technology, Faculty of Geodesy and Cartography, Plac Politechniki 1, 00-661Warsaw, Poland

Abstrakt

The article reviews the technology of construction and functioning of watertight elements of hydrotechnical embankments. A case study of two reservoirs located in the middle course of the Nysa Kłodzka River is described: (1) Otmuchów reservoir functioning since 1933, (2) Nysa reservoir functioning since 1971. The effectiveness of the applied impermeable screens, i.e. a clay screen of the Otmuchów reservoir and a concrete screen of the Nysa reservoir, was assessed and compared. Data from piezometers located at the height of the dam crest along its entire profile were analysed for measurements taken in the years 2020–2022. Indicators such as the distribution and depth of the water level in the dam body and changes in pressure in piezometers under the influence of water level fluctuations in the reservoir were considered. In addition, the scale and frequency of repair and maintenance activities carried out on both facilities were analysed, especially in aspects of the dam body sealing and the need to repair the upstream slope structures, which are directly exposed to filtration and wave action. It was found that, despite the long period of operation of both facilities, they maintain proper water tightness, and the depth of the water level in the embankments reacts only slightly to fluctuations in the amount (height) of stored water. This correlation is more evident closer to the middle part of the dam of the Nysa reservoir, where an abrupt increase in damming height caused a vertical movement of the water table in the embankment, but with a delay of about a week. It was pointed out that both sealing technologies adopted were associated with the need for numerous revitalisation measures, mainly due to dynamic degradation of the stone paving in the area of fluctuations in the level of dammed water in the case of the Otmuchów reservoir and loss of watertightness at expansion joints of concrete slabs protecting the upstream slope of the Nysa reservoir dam.
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Autorzy i Afiliacje

Maksymilian Połomski
1 2
Mirosław Wiatkowski
3

  1. Institute of Environmental Engineering,WrocławUniversity of Environmental and Life Sciences,pl. Grunwaldzki 24, 50-363 Wrocław, Poland,
  2. State Water Holding Polish Waters – Regional Water ManagementAuthority in Wrocław, Norwida 34, 50-950 Wrocław, Poland
  3. Institute of Environmental Engineering, Wrocław University of Environmental andLife Sciences, pl. Grunwaldzki 24, 50-363 Wrocław, Poland

Abstrakt

In Europe, half of the amount of sewage sludge from wastewater treatment plants (WWTPs) is used in agriculture, in Poland about 27%, respectively. Fertilizing products (compost or organic-mineral fertilizers) produced from sewage sludge are promise alternative for directly use of no-treated waste. The paper presents seasonal changes of Cu, Pb, Ni, Zn, Cr, Cd and Hg content in sewage sludge from different regions of Poland collected during one year. It was noted wide range of the metal amount in dependence on season andWWTPs capacity. The Cu concentration was from 0.4 to 784 mgkg–1 d.m., Ni from 0.25 to 1281 mgkg–1 d.m., Cd from 0.005 to 14.85 mgkg–1 d.m., Pb from 0.11 to 306.2 mgkg��1 d.m., Hg from<0.001 to 2.3 mgkg–1, Cr from 0.23 to 854 mgkg–1 and Zn from 11 to 4669 mgkg–1, respectively. It has been shown that Cu, Cd, Pb, Hg and Cr content did not exceed the permissible levels for agricultural purposes according to Polish law. There was no clear correlation between the heavy metal amount and the WWTP capacity, expressed as population equivalent (PE). However some increase trend in the case of Cu, Ni, Hg and Cr concentration at the higher PE value was found. It has been concluded that in spite relatively low level of heavy metals in Polish WWTPs, it may be limiting factor for production high quality fertilizers on the base of sewage sludge.
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Autorzy i Afiliacje

Małgorzata J. Kacprzak
1
Hanna Bauman-Kaszubska
1
Karolina Wójcicka
1

  1. Warsaw University of Technology, Faculty of Civil Engineering, Mechanics and Petrochemistry,Institute of Civil Engineering, ul. Łukasiewicza 17, 09-400 Płock, Poland

Abstrakt

The paper briefly describes modern method assessment of the pavement structure based on the simplified viscoelastic continuum damage (S-VECD) model. The method was used to compare two types of pavement structures. There were analysed classical cstructures with asphalt concretes with neat bitumen and innovative one- or two layered structures with SMA 16 with highly polymer modified bitumen (HiMA). Pavement structures using SMA 16 are especially recommended for local roads, thus two traffic categories were analysed – light and medium. Furthermore, due to specific properties of layers with HiMA, for each variant two different types of improved sub-base were checked. The examples presented, despite reduced thickness of asphalt layers, structures with SMA 16 HiMA are much more resistant to fatigue than classic structures with asphalt concretes with neat bitumen. The results of the research confirm that it is possible to develop innovative structures with materials with above standard properties. New materials both with new arrangement of layers can bring a lot of advantages especially in the areas of sustainable development, costs reducing and improving properties of asphalt pavements.
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Autorzy i Afiliacje

Przemysław Ostrowski
1
ORCID: ORCID
Adam Zofka
2
ORCID: ORCID
Krzysztof Błazejowski
3
ORCID: ORCID
Marek Pszczoła
1
ORCID: ORCID

  1. Gdansk University of Technology, Faculty of Civil Engineering, ul. Gabriela Narutowicza 11/12, 80-233Gdansk, Poland
  2. Foundation for the Development of Transport Infrastructure Services (FRUIT)
  3. ORLEN Asfalt, ul. Łukasiewicza 39, 09-400 Plock Poland

Abstrakt

In civil engineering applications, alongside inherent resistance, the moisture content in wood is one of the most important factors affecting the durability of wood. The moisture content of wood is significantly influenced by the moisture diffusion coefficient. In this study, the impact of considering humidity fluctuations in a climatic chamber during the sorption process on the computational values of functional coefficients in various models of diffusion coefficient variability with material moisture content was analyzed. The dependence of the moisture diffusion coefficient on moisture concentration in wood was assumed in the form of constant, linear, quadratic, and exponential functions. The coefficients in the sought-after functions were found using the error function minimization method based on the kinetics of moisture sorption measurements in samples of Scots pine in the radial and tangential directions at an average air humidity in the chamber of 32%. As a result of the calculations, it was found that taking into account humidity fluctuations in the climatic chamber improved the fitting of computational curves to experimental curves in the case of constant and exponential models. The values of the diffusion coefficient assumed as constant calculated assuming variable humidity conditions in the chamber, differed on average by about 4% compared to the values of these coefficients obtained without considering air humidity fluctuations. In the case of each analyzed sample, the linear descriptions of the variability of the diffusion coefficient had a less steep course when considering air humidity fluctuations in the climatic chamber during the calculation process.
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Autorzy i Afiliacje

Anna Wicher
1
Jadwiga Swirska-Perkowska
1
Sławomir Pochwała
2

  1. Opole University of Technology, Faculty of Civil Engineering and Architecture, ul. Katowicka 48,45-061 Opole, Poland
  2. Opole University of Technology, Faculty of Mechanical Engineering, ul. S. Mikołajczyka 5,45-271 Opole, Poland

Abstrakt

This paper describes the author’s method for the direct and continuous measurement of the temperature distribution during the initial period of hardening concrete, together with the results of tests obtained with its use. The first successful test using this method was conducted by the author in May 2001 [7]. In the following years, the author successfully used this method in the study of other structural elements [8] and [9]. He independently developed and made the necessary elements to measure the temperature in hardening concrete. The tested element is a reinforced concrete column with a diameter of 2.0 m and a height of 8.0 m, which is an intermediate support for the flyover under construction along the Wrocław city ring road. The structure consists of two independent continuous 15-span structures made of pre-stressed concrete (Fig. 1). The article additionally presents numerical model of the previously tested reinforced concrete pillar and the calculation results obtained. The numerical calculations were carried out using the Abaqus FEA software [1]. In conclusions, the author summarises the important elements of the on-site test and makes recommendations for further use of this method to predict the temperature distribution in other elements of the structure, provided that they are made of exactly the same concrete mixture.
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Autorzy i Afiliacje

Andrzej Helowicz
1
ORCID: ORCID

  1. Wrocław University of Science and Technology, Faculty of Civil Engineering,Na Grobli 15, 50-421 Wrocław, Poland

Abstrakt

Form-finding of cable nets is the main topic of this paper. This initial stage of design path is grounded on the enhanced version of the Force Density Method. Apart from the basic form-finding it includes optimal shaping and adding self-weight of a cable structure. Minimal sum of cable lengths in the structure is treated here as a favourable initial configuration for reaching geometry and force distribution under prestress and self-weight. Regarding tensile forces obtained this way, cable sections can be proposed as the first approximation in further design process not included in this analysis. The basics of classic version of the Force Density Method are introduced in the paper. The nonlinear version of this method is used to solve an optimization problem of minimum weight cable net. The essentials of the procedures for achieving optimal shape and adding self-weight are also included and constitute the Extended Force Density Method proposed by the author. Defining proper input data for the self-weight analysis is crucial to find a new shape possibly close to the optimal one and is also discussed. A few examples of optimal or partially optimal cable nets are presented. It is shown that adding self-weight and elastic material properties can preserve the optimal shape with high accuracy. This allows to switch from the purely geometric problem of form-finding to the initial form of a structure with assumed sections and material. All calculations are performed with the use of the self-developed program UC-Form which is also briefly presented.
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Autorzy i Afiliacje

Izabela Wójcik-Grząba
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw,Poland

Abstrakt

The COVD-19 pandemic has changed the mobility patterns of city dwellers worldwide. These changes apply to the number of trips made, their durations and directions as well as transport modes chosen for travelling purposes. In general, although the number of trips decreased, the use of cars increased and that of public transport declined. These mobility changes were induced by the fear of travelling in crowded vehicles and the extent of restrictions introduced by the governments. The effects of such changes are hard to assess and their evaluation is a complex issue. Based on data available about the transportation system in Warsaw and analysis of Big Data (comprising SIM card movements, acquired from mobile phone network operators), a research project has been carried out under the “IDUB against COVID-19” programme. Transportation models had been built which enabled estimation of the number of trips made at each stage of the pandemic in the spring 2020 and identification of differences through comparison with the models developed for the pre-pandemic conditions (year 2019). The calculations enabled assessment of the social costs of the pandemic associated with the urban transportation system, brought about mostly by changes in using private and public transport modes. The cost efficiency of public transport decreased as a result of limits on the number of passengers per vehicle introduced by transport authorities.
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Autorzy i Afiliacje

Andrzej Brzezinski
1
Tomasz Dybicz
1
Karolina Jesionkiewicz-Niedzinska
1
Piotr Olszewski
1
ORCID: ORCID
Beata Osinska
1
Piotr Szagała
1
Łukasz Szymanski
2

  1. Warsaw University of Technology, Faculty of Civil Engineering, al. Armii Ludowej 16, 00-637 Warsaw, Poland
  2. Transeko, ul. Sniadeckich 20/13, 00-656 Warsaw, Poland

Abstrakt

Container settlements (CS) have been widely used as emergency and temporary dwellings in Europe due to the advantages of rapid deployment, cost-efficiency and relatively good living standards. Nevertheless, many authors emphasize the risks of disturbing the spatial order and stigmatization of residents that can lead to deepening the feeling of unrooting and generate substantial social problems. The purpose of the article is to demonstrate the main architectural characteristics of CS built in Ukraine to address internal migration caused by war. Multiple comparative case study includes 18 settlements built for internally displaced persons (IDPs) in three distinctive phases. The research focuses on the features critical to human comfort and life quality: settlement size, program, building typology, spatial arrangement, circulation, unit layout, degree of privacy. Results show that developments from 2015 and 2022 have similarities including basic program, size of dwelling units and density, but there are important differences related to the time allocated to designing and construction as well as expected period of operation. Basic recommendations for improving existing and planned developments are increasing the privacy by creating collective-private space outside and inside, developing a rich program, use existing greenery and new landscaping, providing good transit to the urban centres, using all-year weatherproof typologies and technical solutions suitable for long-term use. This fact must be considered in the process of designing new CS for IDPs and refugees, that are being planned and constructed in Ukraine and Europe.
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Autorzy i Afiliacje

Oksana Pekarchuk
1
Łukasz Piątek
1
Anna Tofiluk
1
ORCID: ORCID
Marta Cygan
1
Agnieszka Nowacka
1

  1. Warsaw University of Technology, Faculty of Architecture, ul. Koszykowa 55, 00-659 Warsaw, Poland

Abstrakt

The saturated metasandstone is taken as the research object, and the uniaxial compression characteristics of the saturated metasandstone are simulated by means of the artificially made saturated sandstone samples. By checking the parameters of the Particle Flow Code (PFC) numerical simulation of loading and unloading seepage stress coupling, the effects of the conductivity coefficient, the pipe diameter, the apparent volume of the domain and the time step on the calculation results are analyzed. When PFC is used for numerical simulation of seepage stress coupling, the conductivity coefficient K can be taken as 0.010. When the pipe diameter is 1.0 mm, the apparent volume of the current domain is 1 x 10–6 m3, the water pressure distribution inside the sample is relatively uniform. The influence of time step on the compressive strength and peak strain of the specimen can be almost ignored. Under the action of water pressure, the compressive strength of the intact rock like sample and the rock like sample with cracks decreases, and the compressive strength of the sample decreases gradually with the increase of water pressure. When the inclined angle of fracture is the same, the seepage pressure is the same, and the confining pressure is the same, the compressive strength of the specimen also increases with the increase of the initial axial stress level during unloading. When the confining pressure and the osmotic pressure are the same, the unloading effect makes the crack development of the specimen faster and more complete, the specimen is more fragmented and multiple parallel shear bands develop.
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Autorzy i Afiliacje

Liangxiao Xiong
1
ORCID: ORCID
Haijun Chen
2
ORCID: ORCID
Zhongyuan Xu
3
ORCID: ORCID
Deye Hu
4
ORCID: ORCID

  1. School of Civil Engineering and Architecture, East China Jiaotong University, Nanchang330013, China
  2. Geotechnical Engineering Department, Nanjing Hydraulic Research Institute, Nanjing, 210029, China
  3. Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 611756, China
  4. School of Civil Engineering and Architecture, East China Jiaotong University, Nanchang 330013, China

Abstrakt

The model presented in this paper was prepared to determine the pile toe resistance mobilization mechanism. Due to the fact, that skin resistance of piles was widely analyzed by the Authors in previous papers [1,2] which were based on both field and laboratory test results, currently the main focus is to describe the mobilization of pile toe resistance. The physical experimental model consists of a chamber measuring 2.2 m, 2.4 m and 6.0 m in width, length, and height, respectively, filled with cohesionless soil. The model has a hydraulic cylinder to apply force at the pile head and equipment to measure pile settlement with force mobilized at the pile base. The purpose of this research was to verify previously formulated methods referring to the M–K curves. Furthermore, the research allowed us to examine if the relationship between pile toe resistance and force applied at the pile head is linear. As a result of the tests, it was confirmed that for purposes of practical engineering calculations, the resistance of the pile toe can be described regarding the load, which is applied at the pile head. The description of this relationship is presented with M–K curve parameters.
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Autorzy i Afiliacje

Zygmunt Meyer
1
Paweł Siemaszko
2
Krzysztof Zarkiewicz
2

  1. West Pomeranian University of Technology, Faculty of Civil and Environmental Engineering,Szczecin, al. Piastów 50a, 71-311 Szczecin, Poland
  2. West Pomeranian University of Technology, Faculty of Civil and Environmental Engineering, Szczecin,al. Piastów 50a, 71-311 Szczecin, Poland

Abstrakt

This paper presents the results of shear strength tests of fine-grained soil reinforced by randomly oriented fibres. The tests were carried out in a direct shear apparatus on samples with a diameter of 100 mm and a height of 20 mm. The samples were formed directly in the apparatus box at a natural moisture content and two values of the degree of compaction (IS = 0:79 and 0.90). The studies were carried out for samples of natural moisture content and for soaked ones. The two types of polypropylene fibres were used: monofilament and fibrillated (of traded names Fibermesh 300-e3 and SikaCem Fiber-12, respectively). The fibre content was 0.25; 0.50 and 1.00% by the weight of the dry soil. The results showed that the presence of fibre within the soil increased its the shear strength. The improvement of the shear strength was related to the type of reinforcement, its content and the soil parameters. The maximum increase in shear strength was 47% compared to the shear strength of the unreinforced soil. The increase in shear strength values were related mainly to the increase in the angle of internal friction of the soil. It was found that as the degree of compaction of the soil increases, the higher enhance of the shear strength of reinforced soil occurs. It was also found that the improvement of shear strength of reinforced soaked samples was more significant than for un-soaked ones.
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Autorzy i Afiliacje

Tymoteusz Zydron
1
Andrzej Gruchot
1
ORCID: ORCID
Dominika Zawiła
2
ORCID: ORCID

  1. University of Agriculture in Kraków, al. Mickiewicza 21, 31-120 Kraków, Poland
  2. Olbrych-Malik s.c., ul. na Szaniec 13/6, 31-560 Kraków, Poland

Abstrakt

The present study is focused on experimental investigations of mechanical properties of 3D-printed tensegrity-inspired metamaterials. Tensegrity systems have many advantageous features, such as: light weight, high stiffness-to-mass ratio, controllability, inherent attributes of smart structures, and unique mechanical behaviour. They may be applied not only in macro-scale, but they can also be used to create cellular mechanical metamaterials and lattices in various scales. Metamaterials are understood here as human-designed artificial materials, which do not exist in nature, and whose mechanical properties result from the morphology of the inner structure rather than from chemical or phase composition. Experimental studies on tensegrity metamaterials manufactured using 3D printing techniques are hardly present in the literature. This paper presents results of uniaxial compression tests carried out on a number of 3D-printed tensegrity-based modules corresponding to the metamaterial cells, differing in the manufacturing technology, parent material, and size. The following observations were made during the tests: one of the most important parameters that has a direct impact on the results is the elongation at break of the parent material; any inaccuracies at the production stage greatly affect the mechanical behaviour of the structure; it is crucial to ensure a free deformation consistent with the infinitesimal mechanism mode of tensegrity; a post-critical behaviour of the struts was clearly visible in the performed tests.
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Autorzy i Afiliacje

Anna Al Sabouni-Zawadzka
1
ORCID: ORCID
Wojciech Gilewski
1
ORCID: ORCID
Adam Zawadzki
2
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw,Poland
  2. Warsaw University of Technology, Faculty of Automotive and Construction Machinery Engineering,Narbutta 84, 02-524 Warsaw, Poland

Abstrakt

Engineering management is an extremely important aspect of construction engineering, and a better management approach can greatly enhance the production profits of enterprises. Traditional management optimization schemes cannot adapt to current technological needs due to their inability to effectively consider the impact of each factor. Therefore, a construction management optimization scheme combining improved particle algorithm and multi-objective optimization was proposed. The improved particle algorithm enhances its performance by introducing adaptive weight and multi-objective optimization ideas. These studies confirmed that the predicted direct cost savings for the project were around 1 million yuan. The total construction period of project was optimized to 380 days, saving 34 days. The optimization technology not only reduced construction costs, but also reflected the problems that could be improved during this construction process. This study contributes to achieving multi-objective balance in the construction management process, effectively improving project efficiency, reducing project costs and risks, and providing scientific support for construction decision-making.
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Autorzy i Afiliacje

Xu Liu
1
ORCID: ORCID

  1. Management of State-owned Assets Department, Sichuan Water Conservancy Vocational College, No.366Yonghe Avenue, Chongzhou, China

Abstrakt

Permeable concrete has the characteristics of breathability, permeability, and high heat dissipation. To improve its mechanical and frost resistance properties, this study optimized the preparation and performance of permeable concrete by adding materials to improve its performance. The performance analysis validate that epoxy resin owns a filling effect on the pores of permeable concrete. The internal curing agent, high water absorbent resin, has a good water absorption effect. The synergistic effect of these two increases the density and compressive strength of permeable concrete. When the two contents are 0.5%, the maximum compressive strength of modified permeable concrete at 7 and 28 days was 15.62 and 17.97 MPa, respectively. Under the action of freeze-thaw cycles, its mass loss rate show an upward trend By comparison, epoxy resin and high water absorbent resin are beneficial for improving the frost resistance of permeable concrete. The minimum value of relative dynamic modulus of elasticity remains stable at over 80%, and the loss rate of dynamic modulus of elasticity is all below 0.4. However, the influence of epoxy resin and SAP on the mass loss rate is relatively small, and the mass loss of all experimental groups is controlled below 2.5%. The binomial Fourier function model is the best predictive model for permeable concrete under freeze-thaw cycles. This study has positive significance for improving the performance of permeable concrete and maintaining the sustainable development of ecological cities.
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Autorzy i Afiliacje

Lili Wei
1
ORCID: ORCID

  1. School of Resources Environment and Architectural Engineering, Chifeng University,Chifeng 024000, China

Abstrakt

Pore structure is a key parameter used to evaluate reservoir quality. At present, experimental method is the most important method to analyze reservoir pore structure. However, coring data may be limited, and it is not possible to perform experimental analyses on all cores. Therefore, the researchers explored the use of logging techniques to study the pore structure of reservoirs. The relationship between pore geometry index (PGI), pore permeability and mercury injection parameters was analyzed based on mercury injection experiment, thin slice analysis, production test data and well logging data. These results can then determine the response characteristics of the logging parameters that correspond to different pore structures and establish a method of modeling the PGI through a multiple parameter regression and neural network method. This research shows that: (1) PGI can quantitatively characterize pore structure, and the maximum pore throat radius, displacement pressure and flow unit index have the highest correlation with PGI, which can be accurately characterized by practical formulas; (2) Natural gamma ray, natural potential amplitude difference, acoustic transit time, density, compensated neutron, deep and shallow resistivity logging data can reflect the quality of the reservoir pore structure. However, there are limitations in evaluating reservoir pore structure with a single logging parameter. Multi-parameter regression method and neural network method realize the quantitative calculation of pore structure from the perspective of multi-parameter and nonlinear. (3) The neural network method and multiple parameter regression method are used to study the pore structure of reservoir and realize the continuous quantitative calculation of pore structure index in a single well. It can be used in uncored analysis Wells and as one of the parameters to evaluate reservoir pore structure.
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Autorzy i Afiliacje

Gaorun Zhong
1
Yajun Li
1
Yuhan Tan
2

  1. School of Petroleum Engineering and Environmental Engineering, Yan’an University, Yan’an 716000, China
  2. CNLC Geology Research Institute, Xi’an 710077, China

Abstrakt

An in-depth understanding of the mechanical properties and damage and fracture mechanism of selected rocks in a diversion tunnel plays an important role in promoting the efficient construction and safety of rock blasting excavation in a diversion tunnel. To study the mechanical properties and damage evolution characteristics of selected rocks in diversion tunnels under uniaxial loading, the uniaxial compression and uniaxial splitting tests of granite and tuff were carried out. In terms of mechanical properties, the evolution characteristics of complete stress-strain curves, instantaneous modulus-strain curves, and input energy density-strain curves were analyzed. In the aspect of damage characteristics, the macroscopic and mesoscopic failure modes were analyzed and the damage fracture mechanism was revealed. Compression-shear failure mainly occurred in granite and tuff under uniaxial compression, showing the characteristics of elastic-brittle fracture failure. Both granite and tuff showed a failure mode of coexistence of “compression-shear failure zone at the loading ends” and “tension-shear failure zone in the middle” under uniaxial splitting. The compression-shear fracture of granite was relatively smooth, and the matrix and mineral particles produced fine particles due to friction in the process of shear slip. The compression-shear fracture of tuff was relatively rough and the characteristics of shear slip were not prominent enough. The fracture failure of granite and tuff was mainly caused by the common fracture of rock matrix and mineral particles. Based on the Lemaitre equivalent strain principle, the pre-peak-post-peak two-stage damage constitutive model established by Weibull statistical distribution theory can accurately describe the static stress-strain relationships of granite and tuff under uniaxial compression.
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Autorzy i Afiliacje

Rongzhou Yang
1
ORCID: ORCID
Ying Xu
2
ORCID: ORCID
Yonghui Lai
3
ORCID: ORCID
Suqian Ni
4
ORCID: ORCID
Fengfeng Feng
5
ORCID: ORCID

  1. School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan232001, China
  2. School of Civil Engineering and Architecture, Anhui University of Science and Technology,Huainan 232001, Chin
  3. Zhejiang Tunnel Engineering Group Co., Ltd., Hangzhou 310000, China
  4. School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan 232001,China
  5. 5Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan 232001, China

Abstrakt

In light of the current situation where excessive amounts of excavated earth from subway tunnel construction are being stacked with low utilization and value, this study used residue as a mineral admixture to investigate the effects of different proportions of residue content (0%, 2.5%, 5.0%, 7.5%, and 10.0%) on the workability and mechanical properties of C50 concrete. The results indicate that: (1) The initial slump and slump loss of C50 concrete decrease gradually as the residue content increases. (2) The compressive strength of C50 concrete with varying residue contents is lower than the control group at early stages (3d, 7d), while it is higher than the control group at 28d. There exists an optimal content of residue for improving C50 concrete compressive strength, and it is found that the highest compressive strength at 28d is achieved when the residue content is 7.5% of the cement content. (3) The microscopic structure of C50 concrete with different residue contents at 28d shows that as the residue content increases, the microscopic structure of C50 concrete gradually becomes more compact and the porosity decreases.
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Autorzy i Afiliacje

Xiaochun Zhao
1
ORCID: ORCID
Meijiu Zhao
2
ORCID: ORCID

  1. Vocational University of Science and Technology, School of Urban Construction, No.18 QiongshanAvenue, Haikou, China
  2. Hainan Vocational University of Science and Technology, School of Urban Construction, No.18 QiongshanAvenue, Haikou, China

Abstrakt

Reclamation from the sea is a method of expanding urban area, but it also faces the problem of difficult treatment of soft soil foundation by hydraulic reclamation. Therefore, a soft soil consolidation method that combines vibration pressure boosting drainage and piled-load static pressure stacking is now proposed. To verify the effectiveness of this method, a consolidation test based on soft soil samples was designed and conducted in the study. The test results showed that when the sampling height was 240mm, the overall moisture content of the consolidated soil sample was the highest, 44.3%, and the consolidation effect was the worst. When the sampling height was 140mm, the overall moisture content obtained from the test was the lowest, 43.1%, and the consolidation effect was the best. The displacement of corner 2 and center point at the intersection of the preceding and following periods was greater, with values of 37.1 mm and 39.2 mm, respectively. At this point, the displacement of corner 1 was significantly smaller, at 30.9 mm. In the later loading stage, the slope of the vertical displacement curve significantly increased. When the experimental time reached 7000 min, the mixed method designed in this study had a drainage rate of 0.53 ml/min, which was significantly higher than other traditional methods. The experiment outcomes indicated that the method designed in this study had certain application potential for improving the consolidation effect of soft soil foundation in hydraulic fill sites.
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Autorzy i Afiliacje

Wei Zhang
1
ORCID: ORCID

  1. Mining Engineering, Shanxi Institute of Energy, Taiyuan, 030600, China

Abstrakt

In response to the current issue of poor modeling performance of Building Information Modeling for building models, a new Building Information Modeling based on an improved region growth algorithm is proposed. This method improves the region growth algorithm by introducing machine learning technology, and utilizes the improved algorithm to perfect the building model, thereby improving the efficiency of Building Information Modeling. The performance comparison experiment of the improved algorithm shows that its accuracy is 92.3%, respectively, which are lower than the comparison algorithm. Subsequent empirical analysis found that the robustness rating of the renovated building with the new Building Information Modeling was 94.06, significantly higher than the traditional model. The above results indicate that the new Building Information Modeling proposed in the study has high efficiency and accuracy in building reinforcement and renovation. This method can provide a new solution and idea for the field of building reinforcement and renovation.
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Autorzy i Afiliacje

Cong Du
1
ORCID: ORCID
Yi Wen
2
ORCID: ORCID
Lijian Ren
1
ORCID: ORCID

  1. School of Civil Engineering, Inner Mongolia University of Technology, Hohhot, 010010, China
  2. College of Architecture, Inner Mongolia University of Technology, Hohhot, 010010, China

Abstrakt

To save resources and protect the environment to the maximum extent, green buildings came into being. Among them, prefabricated building is the only way for traditional buildings to transform into green buildings. The construction scheduling of traditional buildings is mostly focused on the control of on-site resources, which cannot scientifically and reasonably complete the construction goal of prefabricated building. In response to the above issues, a resource constrained scheduling model based on genetic algorithm is designed by sustainable development, and an improved non dominated sorting genetic algorithm with elite strategy is introduced. It is used to solve the time cost weight balance scheduling model and the low-cost low-carbon scheduling model. The research results indicated that this algorithm had a reverse generation distance value of 0.35 when evaluated 4000 times, and a super volume value of 0.43 when evaluated 10000 times. In the application of a certain affordable housing project, the resource constrained scheduling model based on genetic algorithm can shorten the assembly phase to 8 days, and the low-cost low-carbon scheduling model using proposed algorithm can reduce the transportation cost and carbon emission duration of transportation vehicles to 22501 yuan and 93.75 h, respectively. Resource constrained scheduling models based on genetic algorithms and low-cost low-carbon scheduling models have potential in the field of green buildings, which can achieve significant results in saving time, cost, and reducing carbon emissions. These research results can provide reference for the promotion and practice of green buildings, and guide the formulation and implementation of relevant policies.
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Autorzy i Afiliacje

Chuanguang Yang
1
ORCID: ORCID

  1. College of Architecture and Engineering, The Open University of Shaanxi, Xi’an, 710000, China

Abstrakt

Alkali-activated slag has been noted as one of potential alternatives to the ordinary Portland cement due to its properties including high early strength performance and capability of ambient curing. However, there is still limited studies available on elucidating the reaction processes towards producing the excellent properties. This study aims to elucidate the mechanism of alkali activation of slag under different molarities of sodium hydroxide, which is one of the most influential factors on the properties of alkali-activated slag. Heat evolution of alkali-activated slag was used as a real-time monitoring technique. For mix designation, the molarity of sodium hydroxide was varied from 6M to 14 M, with solid-to-liquid ratios of 0.6 and alkali activator ratios of 2.0 remaining constant. The calorimetric data obtained was further used for determination of degree of reaction, nucleation and growth rate mechanism using Johnson–Mehl Avrami Kolmogrov model. According to the findings, it was found that regardless of various molarity of sodium hydroxide applied, the nucleation mechanism and growth is governed by instantaneous heterogeneous nucleation with rod-like growth as the n value is approaching 1 in which is observed from the morphology of the alkali-activated slag at lowest molarity applied (6 M). Furthermore, increasing in molarity of sodium hydroxide was found to decrease the total heat evolved and the lowest was obtained when using 14 M.
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Autorzy i Afiliacje

Rosnita Mohamed
1
ORCID: ORCID
Rafiza Abd Razak
2
ORCID: ORCID
Mohd Mustafa Al Bakri Abdullah
3
ORCID: ORCID
Shayfull Zamree Abd Rahim
4
ORCID: ORCID
Nurul Aida Mohd Mortar
5
ORCID: ORCID
Liyana Jamaludin
6
ORCID: ORCID
Marcin Nabialek
7
ORCID: ORCID

  1. Faculty of Chemical Engineering and Technology, University of Malaysia Perlis (UniMAP), Perlis, Malaysia;Geopolymer and Green Technology, Centre of Excellence (CEGeoGTech), University of Malaysia Perlis (UniMAP), Perlis, Malaysia
  2. Faculty of Civil Engineering and Technology, University of Malaysia Perlis (UniMAP),Perlis, Malaysia; Geopolymer and Green Technology, Centre of Excellence (CEGeoGTech), University of Malaysia Perlis (UniMAP), Perlis, Malaysia
  3. Faculty of Chemical Engineering and Technology, University of Malaysia Perlis (UniMAP), Perlis, Malaysia; Geopolymer and Green Technology, Centre of Excellence (CEGeoGTech), University of Malaysia Perlis (UniMAP), Perlis, Malaysia
  4. Faculty of Mechanical Engineering and Technology, University Malaysia Perlis (UniMAP), Perlis, Malaysia; Geopolymer and Green Technology, Centre of Excellence (CEGeoGTech), University of Malaysia Perlis (UniMAP), Perlis, Malaysia
  5. Faculty of Chemical Engineering and Technology, University of Malaysia Perlis (UniMAP), Perlis,Malaysia; Geopolymer and Green Technology, Centre of Excellence (CEGeoGTech), University of Malaysia Perlis(UniMAP), Perlis, Malaysia
  6. Faculty of Mechanical Engineering and Technology, University of Malaysia Perlis (UniMAP), Perlis,Malaysia; Geopolymer and Green Technology, Centre of Excellence (CEGeoGTech), University of Malaysia Perlis(UniMAP), Perlis, Malaysia
  7. Department of Physics, Faculty of Production Engineering and Materials Technology, CzestochowaUniversity of Technology, al. ArmiiKrajowej 19, 42-200 Cz˛estochowa, Poland

Abstrakt

In response to the common issues in practical training in vocational engineering construction courses, such as dangerous operation of training equipment, insufficient number of training equipment, and ineffective teaching, a vivid and interactive virtual simulation training system was developed using Unity3D software, taking the U-shaped bridge abutment in the course of Bridge Engineering as an example. Detailed introduction to the development and design process of 3D model establishment, ZSpace device adaptation, file format conversion, model rendering and disassembly, model zooming in and out, script writing and function implementation, UI interface design, etc., in order to achieve immersive interaction functions such as free observation, assembly disassembly, and ZSpace integrated VR virtual experience in the virtual simulation training system. The practical results show that the interactive effect simulated through the simulation training system is superior to that of the physical system, which can enhance the sense of experience, improve learning enthusiasm, and deepen the understanding of the knowledge points in Bridge Engineering Drawing Recognition. After the system is successfully established and applied in the training and teaching process, it will provide an important reference for the training and teaching of relevant courses for students majoring in road and bridge engineering, and also enhance the cultivation of high-quality skilled personnel in engineering majors in vocational colleges.
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Autorzy i Afiliacje

Xiaodong Jia
1
ORCID: ORCID

  1. School of Urban Construction Engineering, Chongqing Technology and Business Institute, No. 19 XuefuAvenue, Chongqing, China

Abstrakt

Research on the properties of sandstone in the tunnel environment has been conducted due to the building industry’s rapid development, which is gradually involving underground water. Sandstone used in tunnel construction is susceptible to high perimeter and water pressures as a result of the abundance of sand and gravel close to groundwater, which might result in mishaps resembling collapses. The modified Burgers Model for the Malm dataset is the foundation of this study, which aims to reduce the internal crack extension caused by sandstone’s unloading creep. First, the study increased the material’s Poisson’s ratio in accordance with the Mohr–Coulomb strength criterion and builds a triaxial loading model on its foundation. Next, it analyzed the extension of the fracture surface of sandstone while taking high peripheral pressure and high hydraulic pressure into account. Finally, it discretized the unloading creep of sandstone using the improved Burgers model. On the basis of the model put forward in the study, experimental validation was then done on the Malm dataset. The sandstone would reach the final rupture area without any protection measures in just 10 days, but the model suggested in the study can delay this time to 200 days, while the effects of the other three models would delay this time by 75, 60, and 41 days, respectively. The model’s breadth was indicated by the linear fit value of 0.9827 for 36 experiments. The experimental findings demonstrated that the model suggested in the study can successfully lower the rate of sandstone unloading creep and increase worker safety.
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Autorzy i Afiliacje

Li Song
1
ORCID: ORCID
Fujun Tang
1
ORCID: ORCID
Dehui Kong
2
ORCID: ORCID

  1. Department of Road and Bridge Engineering, Sichuan Vocation and Technical College of Communications,Chengdu, 611130, China
  2. School of Civil Engineering, Southwest Jiaotong University, Chengdu, 610031, China

Abstrakt

A prefabricated concrete column-to-column structure connected by high-strength bolts is proposed. To explore the seismic performance and failure form of the structure, the finite element analysis software is used to simulate the low-cycle repeated load test. The hysteretic curve and skeleton curve of the structure are obtained, and the stiffness degradation law, ductility and energy dissipation capacity of the structure are quantitatively analyzed to evaluate the seismic performance of the structure. The results show that the ductility coefficient of the structure is basically between 2.19 and 4.97, and the ductility coefficient of most specimens is greater than 3.0, indicating that the structure has good ductility and deformation capacity. The equivalent viscous damping coefficients of the specimens are in the range of 0.21–0.29, indicating that the structure has good energy dissipation capacity. In a certain range, increasing the thickness of the end plate has no significant impact on the energy consumption capacity of the structure. The compressive strength of the concrete in the core area is greatly improved under the constraint of the end plate bolts, and end plate bolt connection can well realize the transmission of force and give full play to the performance of materials.
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Autorzy i Afiliacje

Shufeng Li
1
ORCID: ORCID
Hexiang Li
1
ORCID: ORCID
Di Zhao
1
ORCID: ORCID

  1. School of Civil Engineering, Xuchang University, Xuchang, 461000, China

Abstrakt

Building performance in cold regions greatly affects the quality of people living in the building. With the further development of the construction industry, how to improve the energy efficiency of buildings in cold regions has become one of the key issues. The study introduces paraffin phase change capsules as aggregate components on the basis of foam concrete, and then designs a matching energy efficiency analysis method to regulate the concrete parameters, and finally tests the performance of the research method and conducts an application analysis. The experimental results show that in performance simulation testing, the internal surface temperature decreases to 288.2 K at the minimum when the external temperature is 0°C to 4°C. It shows that the research method can effectively analyze the building performance, and the analysis method can optimize the performance of the foam concrete materials proposed in the research, and obtain building materials with better thermal insulation performance than the existing conventional materials. Research can provide certain technical references for building energy conservation in cold regions.
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Autorzy i Afiliacje

Huifang Wang
1
ORCID: ORCID

  1. Department of Architecture Engineering, Yangzhou Polytechnic Institute, Yangzhou, 225127, China

Abstrakt

This study explores the impact of weak acid salt agents (citrate and tartrate) in the mixture and various curing conditions on the properties of supersulfated cement (SSC) mortar. Compressive strength tests were conducted on prism-shaped samples measuring 4 × 4 × 16 cm. A comprehensive analysis of the phase assemblage of hardened products was carried out using X-ray diffraction (XRD), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). The results reveal the abundant formation of ettringite (E) and hydrotalcite (Ht) when weak acid salt agents are added, especially in chloride and sulfate-rich curing solutions, leading to a notable increase in compressive strength, up to 200% compared to the control sample. Furthermore, the study demonstrates a substantial improvement in early and overall strength under temperature-stimulated curing conditions, accelerating the hydration reaction of SSC. These findings provide deeper insights into the factors influencing SSC hardening and strength development, offering valuable information for enhancing the efficiency and utilization of SSC in the construction industry, aligning with the goals of sustainable development.
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Autorzy i Afiliacje

Nguyen Khanh Son
1
ORCID: ORCID
Nguyen Ngoc Tri Huynh
1
ORCID: ORCID
Thanongsak Imjai
2
ORCID: ORCID
Mohd Mustafa Al Bakri Abdullah
3
ORCID: ORCID
Katarzyna Błoch
4
ORCID: ORCID

  1. Ho Chi Minh City University of Technology - VNU-HCM, Faculty of Materials Technology, Ho ChiMinh city, Vietnam
  2. Walailak University, School of Engineering and Technology, Nakhonsithammarat, Thailand
  3. Centre of Excellence Geopolymer and Green Technology (CEGeoGTech), Universiti MalaysiaPerlish (UniMAP), Perlis, Malaysia
  4. Czestochowa University of Technology, Department of Physics, Faculty of Production Engineeringand Materials Technology, al. ArmiiKrajowej 19, 42-200 Cz˛estochowa, Poland

Abstrakt

Corrugated steel structures buried in the surrounding soil are currently used worldwide in road and railway engineering as culverts, pedestrian and animal crossings, tunnels and bridges. The need of large span corrugated steel structures is rapidly growing however their behavior analysis is still understudied. There is also a lack of discussion about the impact of additional strengthening elements for the behavior of corrugated steel structures. This study analyses the influence of rational steel mesh layout on the behavior of a large span deepest corrugation steel structure. The numerical two-dimensional model of two-radius 17.5 m span profile with corrugation of 237 mm depth and 500 mm pitch was developed to replicate the ongoing project in Lithuania. Originally the stiffness of the structure from both sides was increased by six layers of steel meshes as lateral support. Nevertheless, the current study was looking for rational steel mesh layout. Also, the influence of different layouts of steel mesh on corrugated steel plate utilization to buckling failure in the peaking, dead load and in the most unfavorable live load location phase was analyzed. The finite element model results indicated that steel meshes could be used to control structure deformations and internal reactions. Vertical displacement of the crown of the structure could be reduced by 45% in the peaking phase when using proper steel meshes layout. Furthermore, steel meshes could be a decisive factor for the bearing capacity of corrugated steel structure in a positive sense.
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Autorzy i Afiliacje

Nerijus Bareikis
1
ORCID: ORCID

  1. Vilnius Gediminas Technical University, Faculty of Civil Engineering, Saul˙etekio al. 11, LT-10223Vilnius, Lithuania

Abstrakt

Implementation of sustainability principles in civil engineering has increased the substantive range of bridge engineering. The consideration of additional criteria, in particular ecological and social ones, requires the design process to be supported by appropriate tools. It refers especially to large bridge elements which affect their load-bearing capacity, e.g. girders or decks. The aim of this paper is to develop an original MCDA (Multi-Criteria Decision Analysis) method as a potential tool to support a decision-making process in the selection of material and design alternatives for bridge main girders. Therefore, an advanced hybrid algorithm was created consisting of the following methods: EA FAHP+FDEMATEL+ZUM (Extent Analysis Fuzzy Analytic Hierarchy Process + Fuzzy Decision-Making Trial and Evaluation Laboratory + Zero Unitarization Method), applied at the structure design stage. The pre-dimensioned alternatives selected for analysis were then subjected to an evaluation process based on a complex set of criteria arranged in a hierarchical control structure (HCS). The algorithm has been applied based on the example of a medium span slab-and-girder bridge, assuming 6 alternative concepts of girders, different in material and dimensions. The hybrid method was compared with the EA FAHP method. Analysis results obtained based on judgments from 3 teams of Decision Makers (DM) indicate effectiveness of the proposed algorithm and its practical aspect, which may contribute to improved quality and safety of bridge structures.
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Autorzy i Afiliacje

Przemysław Jakiel
1
ORCID: ORCID
Dariusz Fabianowski
1
ORCID: ORCID

  1. Opole University of Technology, Faculty of Civil Engineering and Architecture, ul. Katowicka 48,45-061 Opole, Poland

Abstrakt

Geotechnical design includes construction works in the course of which the soil is subjected to vertical repetitive stress in the process of compacting, for example in the case of embankments or landfills. When the stress exceeds the pre-consolidation threshold there emerges accumulation of permanent deformation, usually horizontal, which causes additional lateral stress. A rule verified by long-term practical use was presented for to determine the horizontal stress resulting from mechanical pre-consolidation. Independent mathematical analysis has confirmed that the boundary ranges of the cyclic lateral stress factor correspond to the active or reactive states of strain. In geotechnical practice it is the reactive states, in which additional accumulation of lateral strain occurs in soil, that are important.
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Autorzy i Afiliacje

Mirosław Bukowski
1
ORCID: ORCID
Rafał Kuszyk
1
ORCID: ORCID
Maciej Maslakowski
1
ORCID: ORCID

  1. University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw,Poland

Abstrakt

Offsite construction technologies are developed to reduce project cost and duration. To make the most of the potential offered by prefabrication the planner should consider the whole supply chain. A failure to coordinate the off-site production with on-site erection is a source of waste (waiting time of the construction crews or redundant handling activities on-site). Most of the research to date focused on optimizing operations of a prefabrication plant assuming a deterministic schedule of demand for its products. The purpose of this paper is to develop a mathematical model for integrated scheduling of offsite and on-site operations. Its solution is a schedule that minimizes the downtime of both the prefabrication plant and the on-site erection crews. In accordance with the Just-in-Time concept, the prefabrication schedule is set in a way to reduce the stocks of finished products, thus reducing the storage area and cost of funds tied up in inventory. The schedule’s robustness against the disturbance in the production and erection workflows is assumed to be assured allocating time buffers. The advantage of the proposed method is the ease of collecting the input: instead of detailed cost records, estimates of unit cost of lost time can be used.
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Autorzy i Afiliacje

Piotr Jaskowski
1
ORCID: ORCID
Sławomir Biruk
1
ORCID: ORCID
Michał Krzeminski
2
ORCID: ORCID

  1. Lublin University of Technology, Faculty of Civil Engineering and Architecture, Nadbystrzyckastr. 40, 20-618 Lublin, Poland,
  2. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637Warsaw, Poland

Abstrakt

Data synergy involves acquiring and combining data from different sensors to achieve better problem analysis and research results. For more comprehensive data analysis, the sensors are not only mounted on one platform. Still, they should also be compatible with software and hardware, e.g. for the same timestamp registration by different sensors. The aim of this article is to propose the synergy between various remote sensing sensors including the ground penetrating radar (GPR), LiDAR (Light Detection and Ranging) sensor and three photogrammetric RGB cameras for damage detection in a pavement in a park alley. The data were acquired with a low-cost platform, in the Pole Mokotowskie Park in Warsaw, Poland. Three drives were made along the same path with the platform, so it was possible to assess the repeatability of the data. Based on the GPR data, orthophotomap, and digital terrain model (DTM) from images, an analysis of the cracks in the pavement was done. The paper proves additive value from the synergy of data collected for the alley also in the form of a common visualization of acquired data. Results presented in the article showed that using mobile mapping platform and technologies describing the situation above and below the ground level enable a more detailed analysis and inspection of the damages in the park alley.
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Autorzy i Afiliacje

Magdalena Pilarska-Mazurek
1
ORCID: ORCID
Krzysztof Bakuła
1
ORCID: ORCID
Jakub Górka
1
ORCID: ORCID
Paweł Czernic
1
ORCID: ORCID
Anna Lejzerowicz
2
ORCID: ORCID
Wojciech Ostrowski
1
ORCID: ORCID
Borys Chetverikov
3
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Geodesy and Cartography, Pl. Politechniki 1, 00-661Warsaw,Poland
  2. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw,Poland
  3. Lviv Politechnic National University, Institute of Geodesy, 6 Karpinskogo str., Lviv, Ukraine

Zasady etyki publikacyjnej

ETHICS POLICY

”Archives of Civil Engineering” respects and promotes the principles of publishing ethics. Being guided by COPE’s Guidelines ( https://publicationethics.org/resources/guidelines) we ensure that all participants of the publishing process comply with these rules, the journal pays special attention to:

Editor Responsibilities
1. Qualifying individual manuscripts for publication only on the basis of: (a) compliance with the guidelines provided to the authors, (b) substantive value, (c) originality, (d) transparency of presentation
2. Deciding whether the paper fulfills all requirements i.e. formal and scientific and which articles submitted to the journal should be published. In making these decisions, the editor may be guided by the policies of the journal’s editorial board as well as by legal requirements regarding libel, copyright infringement, and plagiarism.
3. Evaluating manuscripts for intellectual content without regard to race, gender, sexual orientation, religious belief, ethnic origin, citizenship, or political philosophy of the author(s).
4. Ensuring scientific accuracy and complying with the principle of authorship; making sure that individual authors who contribute to the publication accept its form after the scientific editing
5. Providing a fair and appropriate peer review process.
6. Withdrawing manuscripts from publication, if any information about its unreliability appeared, also as a result of unintentional errors, features of plagiarism or violation of the rules of publishing ethics were identified.
7. Requiring all contributors to disclose relevant competing interests and publish corrections if competing interests are revealed after publication. If needed, other appropriate action should be taken, such as the publication of a retraction or expression of concern.
8. Maintaining the integrity of the academic record, precludes business needs from compromising intellectual and ethical standards, and is always willing to publish corrections, clarifications, retractions, and apologies when needed.
9. Not disclosing any information about a manuscript under consideration to anyone other than the author(s), reviewers and potential reviewers, and in some instances the editorial board members, as appropriate.

Reviewer Responsibilities
1. Cooperating with the scientific editor and / or editorial office and the authors in the field of improving the reviewed material;
2. Being objective and expressing the views clearly with appropriate supporting arguments.
3. Assessing of the entrusted works in a careful and objective manner, if possible with an assessment of their scientific reliability and with appropriate justification of the comments submitted;
4. identifying relevant published work that has not been cited by the authors
5. calling to the editor's attention any substantial similarity or overlap between the manuscript under consideration and any other published data of which they have personal knowledge
6. Maintaining the principle of fair play, excluding personal criticism of the author (s)
7. Maintaining confidentiality, which is not showing or discussing with others except those authorized by the editor. Any manuscripts received for review are treated as confidential documents.
8. Performing a review within the set time limit or accepting another solution jointly with ACE in the event of failure to meet this deadline.
9. Notifying the editor if the invited reviewer feels unqualified to review the manuscript or knows that its timely review will be impossible.
10. identifying relevant published work that has not been cited by the authors
11. Not considering evaluating manuscripts in which they have conflicts of interest resulting from competitive, collaborative, or other relationships or connections with any of the authors, companies, or institutions connected to the submission.

Author Responsibilities
1. Results of original research should present an accurate account of the work performed as well as an objective discussion of its significance. Underlying data should be represented accurately in the manuscript. A paper should contain sufficient detail and references to permit others to replicate the work. Fraudulent or knowingly inaccurate statements constitute unethical behaviour and are unacceptable.
2. The authors should follow the principle of originality, which is submitting only their own original works, and in the case of using the works of other authors, marking them in accordance with the rules of quotation, or obtaining consent for the publication of previously published materials from their owners or administrators;
3. An author should not in general publish manuscripts describing essentially the same research in more than one journal or primary publication. Parallel submission of the same manuscript to more than one journal constitutes unethical publishing behaviour and is unacceptable.
4. Authorship should be limited to those who have made a significant contribution to the conception, design, execution, or interpretation of the reported study and phenomena such as ghostwriting or guest authorship in the event of their detection must be actively counteracted.
5. All authors should report in a Reliable manner the sources they used to create their own study and their inclusion in the attachment bibliography;
6. All those who have made significant contributions should be listed as co-authors. Where there are others who have participated in certain substantive aspects of the research project, they should be named in an Acknowledgement section.
7. The corresponding author should ensure that all appropriate co-authors (according to the above definition) and no inappropriate co-authors are included in the author list of the manuscript, and that all co-authors have seen and approved the final version of the paper and have agreed to its submission for publication.
8. All authors should disclose in their manuscript any financial or other substantive conflict of interest that might be construed to influence the results or their interpretation in the manuscript. All sources of financial support for the project should be disclosed.
9. When an author discovers a significant error or inaccuracy in his/her own published work, it is the author’s obligation to promptly notify the journal’s editor or publisher and cooperate with them to either retract the paper or to publish an appropriate erratum.

Publisher’s Confirmation
In cases of alleged or proven scientific misconduct, fraudulent publication or plagiarism the publisher, in close collaboration with the editors, will take all appropriate measures to clarify the situation and to amend the article in question. This includes the prompt publication of an erratum or, in the most severe cases, the complete retraction of the affected work.

Procedura recenzowania

Manuscript Peer-Review Procedure

”Archives of Civil Engineering” makes sure to provide transparent policies for peer-review, and reviewers have an obligation to conduct reviews in an ethical and accountable manner. There is clear communication between the journal and the reviewers which facilitates consistent, fair, and timely review.

-The model of peer-review is double-blind: the reviewers do not know the names of the authors, and the authors do not know who reviewed their manuscript (but if the research is published reviewers can eventually know the names of the authors). A complete list of reviewers is published in a traditional version of the journal: in-print.
-It is the editor who appoints two reviewers; however, if there are discrepancies in the assessment the third reviewer can be appointed.
-After having accepted to review the manuscript (one-week deadline), the reviewers have approximately 6 weeks to finish the process.
-The paper is published in ACE provided that the reviews are positive. All manuscripts receive grades from 1-5, 5 being positive, 1 negative, the authors receive reviews to read and consider the comments.
-Manuscript evaluations are assigned one of five outcomes: accept without changes, accept after changes suggested by the reviewer, rate manuscript once again after major changes and another review, reject, withdraw.
-Manuscripts requiring minor revision (accept after changes suggested by the reviewer) does not require a second review. All manuscripts receiving a "Rate manuscript once again after major changes and another review " evaluation must be subjected to a second review. Rejected manuscripts are given no further consideration. There are cases when the article can be withdrawn, often upon the request of an author, technical reason (e.g. names of authors are placed in the text, lack of references, or inappropriate structure of the text), or plagiarism.
-The revised version of the manuscript should be uploaded to the Editorial System within six weeks. If the author(s) failed to make satisfactory changes, the manuscript is rejected.
-On acceptance, manuscripts are subject to editorial amendment to suit house style.
-Paper publication requires the author's final approval.
- As soon as the publication appears in print and in electronic forms on the Internet there is no possibility to change the content of the article.

Editor’s responsibilities
-The editor decides whether the paper fulfills all requirements i.e. formal and scientific and which articles submitted to the journal should be published.
-In making these decisions, the editor may be guided by the policies of the journal’s editorial board as well as by legal requirements regarding libel, copyright infringement, and plagiarism.
-The editor maintains the integrity of the academic record, precludes business needs from compromising intellectual and ethical standards, and is always willing to publish corrections, clarifications, retractions, and apologies when needed.
-The editor evaluates manuscripts for intellectual content without regard to race, gender, sexual orientation, religious belief, ethnic origin, citizenship, or political philosophy of the author(s).
-The editor does not disclose any information about a manuscript under consideration to anyone other than the author(s), reviewers and potential reviewers, and in some instances the editorial board members, as appropriate.

Reviewers' responsibilities
Any manuscripts received for review are treated as confidential documents. They must not be shown to or discussed with others except if authorized by the editor. Privileged information or ideas obtained through peer review is kept confidential and not used for personal advantage Any invited reviewer who feels unqualified to review the manuscript or knows that its timely review will be impossible should immediately notify the editor so that alternative reviewers can be contacted. Reviewers should identify relevant published work that has not been cited by the authors. Any statement that an observation, derivation, or argument had been previously reported should be accompanied by the relevant citation. A reviewer should also call to the editor's attention any substantial similarity or overlap between the manuscript under consideration and any other published data of which they have personal knowledge. Reviewers should not consider evaluating manuscripts in which they have conflicts of interest resulting from competitive, collaborative, or other relationships or connections with any of the authors, companies, or institutions connected to the submission. Reviews should be conducted objectively. Personal criticism of the author is unacceptable. Referees should express their views clearly with appropriate supporting arguments. All reviews must be carried out on a special form available in the Editorial System.

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