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Number of results: 22
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Abstract

The compactness of dimension stone blocks was previously controlled through various methods that were partially based on personal experiences, acoustic and visual observance of materials. With the development of technology, the ultrasonic pulse method is frequently used for the examination of stone test pieces and with an analysis of acquired data through the tomography method, the compactness is determined. The monolith stone blocks that are found at a site contain hidden discontinuities. The technique of data acquisition and the use of various instruments enable a good overview of the block interior. With an increased number of measurements, a suitable classification is prepared that helps reduce modification costs and increases the quality of stone blocks. The control methodology of compactness is based on the passage of longitudinal waves through the stone block without damaging the block during control. High differences in speed show irregularities in the material. With the observation system, we can prepare a tomography of the measured profiles that show us the locations of irregularities that should be observed more closely. During in situ measurements, the data for comparison with measured results are acquired. Determination of critical locations is of extreme importance before the processing of the block into smaller stone products or during the reconstruction of older stone elements or sculptures. The purpose of “in situ” measurements is to prepare a simple and fast method for the evaluation of materials compactness and for production work.

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Authors and Affiliations

Andrej Kos
Jože Kortnik
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Abstract

This paper presents data on the management of dimension stones in Poland in the period 2011– –2021. The domestic production of rocks suitable for the production of slabs, pitcher and curbs, etc. is estimated and the major varieties of rocks utilized for these purposes are indicated. Data on raw and processed products with regard to imports and exports are presented for crude and roughly worked blocks and slabs, worked dimension stones as well as pitcher, curbs and other road stones. In the first two groups, data is reported separately for:
- marbles, limestones and other carbonate rocks,
- granites,
- sandstones (distinguished as separate category in crude blocks and slabs group),
- other rocks.
Data on the volume of production, imports and exports is utilized for the calculation of the apparent consumption of dimension stone in Poland. The conducted analyses revealed that its volume has been ranging from 1.4 to 1.9 million tons/year in 2013–2021 with the exception of the years 2011–2012 when it reached ca. 2.7 million tons/year. The most important group of rocks utilized in Poland as dimension stones are granites. These originated primarily from domestic deposits but they are also imported from various directions, primarily from the Republic of South Africa and India (crude blocks and slabs), China (worked dimension stones) as well as from Sweden and Norway in 2011–2012 (significant amounts of hydrotechnical stones). A nother significant group of rocks utilized in Poland as dimension stones are sandstones (with a share of imports in total domestic consumption not exceeding 1%) while marbles, limestones and other carbonate rocks are of marginal importance (primarily imported in the form of worked dimension stones from China, the Czech Republic, Italy and Turkey).
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Authors and Affiliations

Katarzyna Guzik
1
ORCID: ORCID
Beata Figarska-Warchoł
1
ORCID: ORCID

  1. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland
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Abstract

The article presents the problem of selecting the correct type of limestone for producing paving stones used to renovate the surface of Mariacki Square in Krakow. Due to using up local limestone deposits, imported limestones began to be used. The first one was a Turkish limestone with the trade name Lotus Beige. Despite substantial physical and mechanical parameters (compressive strength 134 MPa, water absorption 0.26%), after several years of use, the paving stone cracked and, as a result, fell apart into smaller fragments. Hauteville limestone from France has been selected for the following reconstruction of the surface. This limestone in the air-dry state was characterised by even higher parameters, i.e. compressive strength of 157 MPa, flexural strength at 16.9 MPa, Bohme Abrasion test at 15275 mm3, and water absorption at 0.23%. The tests also showed absolute frost resistance and high resistance to thermal shock. Unfortunately, after several years of using the surface of Mariacki Square, cracks and flaking of the rock material have been observed in terms of some paving stones. These cracks appeared within the so-called stylolite seams, which are a natural feature of limestone. Despite a very strict selection of materials, unfortunately, problems with the surface’s durability could not be avoided.
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Authors and Affiliations

Joanna Hydzik-Wiśniewska
1
ORCID: ORCID
Elżbieta Hycnar
1
ORCID: ORCID

  1. AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow, Poland
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Abstract

The interiors of the Imperial Castle in Poznań are embellished with scores of different stone varieties. In order to preserve and renovate them, an in-depth conservation examination needed to be performed.
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Authors and Affiliations

Maciej Czyński
1

  1. Monument Service
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Abstract

The subject of the research was the Middle Miocene red algal limestone from the Włochy deposit, which is currently the only place of exploitation of the Pińczów Limestone representing a local type of the Leitha Limestone. The collected samples of this rock belong to the organodetric facies of diverse grain size and sorting of clastic material. Considering the proportions of characteristic skeleton remains, the composition of the coarse-grained organodetric facies is red algal-foraminiferalbryozoic, while of the fine-grained facies is foraminiferal-red algal. The cement of these rocks is predominantly sparite compared to micrite-clay matrix. A complement to petrographic studies was the chemical analysis and identification of mineral phases with X-ray diffraction. Moreover, physical and mechanical properties of samples were analyzed. Porosity of the rock was assessed in the polarizing and scanning microscope (SEM-EDS) observations, as well as with a porosimetric tests. The coarse-detrital limestone with a dominant binder in the form of intergranular cement is characterized by the apparent density sometimes exceeded 1.90 Mg/m3, while fine-grained limestone has the highest water absorbability (above 20%) and total porosity (about 40%). The above properties influenced high water absorption by capillarity, limiting the possibility of using limestone in places exposed to moisture. The observed relationship between the ultrasonic waves velocity and the uniaxial compressive strength gives the possibility of predicting the value of the latter parameter in the future. The limestones from Włochy deposit do not differ in quality from the previously used Pińczów Limestones, and their technical parameters predestine them for use as cladding material with insulating properties.

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Authors and Affiliations

Beata Figarska-Warchoł
Grażyna Stańczak
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Abstract

The application of stone column technique for improvement of soft soils has attracted a considerable attention during the last decade. However, in a very soft soil, the stone columns undergo excessive bulging, because of very low lateral confinement pressure provided by the surrounding soil. The performance of stone column can be improved by the encapsulation of stone column by geosynthetic, which acts to provide additional confinement to columns, preventing excessive bulging and column failure. In the present study, a detailed experimental study on behavior of single column is carried out by varying parameters like diameter of the stone column, length of stone column, length of geosynthetic encapsulation and stiffness of encapsulation material. In addition, finite-element analyses have been performed to access the radial deformation of stone column. The results indicate a remarkable increase in load carrying capacity due to encapsulation. The load carrying capacity of column depends very much upon the diameter of the stone column and stiffness of encapsulation material. The results show that partial encapsulation over top half of the column and fully encapsulated floating column of half the length of clay bed thickness give lower load carrying capacity than fully encapsulated end bearing column. In addition, radial deformation of stone column decreases with increasing stiffness of encapsulation material.

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Authors and Affiliations

Y.K. Tandel
C.H. Solanki
A.K. Desai
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Abstract

The authors draw on their experience and past mountain landscape studies to describe an emerging collaborative research project designed to conduct advanced field studies and generate (and test) archaeological landscape models of past hunter-gatherer populations as well as pastoralist and early farming community seasonal transhumance migrations between lowland river valleys of Poland’s Podhale Basin and high altitude forests and meadows its adjacent High Tatra Mountains.

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Authors and Affiliations

Robert H. Brunswig
Paweł Valde-Nowak
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Abstract

Middle Palaeolithic land exploitation strategies remain as yet an unexplored element in our understanding of Neanderthal behavioural patterns. Many different approaches to the problem were so far developed. Among others, biological, economic or environmental data concerning Neanderthals were considered as relevant. One of the focus points in such divagations is the issue of raw materials economy as undertaken by Neanderthals. The long-distance transport of knappable minerals (as a basis for the stone tools production) allows an insight into the economy and understanding of the size of land in use by Neanderthals group. Addressing this particular issue from the perspective of the Western Carpathian Mountains allows us to track the trails of mobility or trace possible contact zones between groups, and also to state, that at least in some circumstances Neanderthal groups were infiltrating and possibly crossing this highly elevated area on the S-N axis.

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Authors and Affiliations

Magda Cieśla
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Abstract

A lithological profile and measurements of the orientation and spacings of natural discontinuity planes were carried out in the Górka-Mucharz sandstone excavation (Krosno Beds, Outer Carpathians, Poland). In addition, the density of the discontinuities was assessed by measuring their spacings using oriented digital photographs of the quarry walls. An orthophotomap was also used in assessing the orientation and density of fractures with the tools available in QGIS. It was shown that digital image analysis can be used as an alternative to direct field measurements, especially in situations where access to an outcrop is difficult. The distributions of spacings larger than 40 cm, obtained by direct measurements and based on digital images of the quarry, were comparable. As a consequence, both measurement techniques yielded similar values of the quantity of blocks (QB), which differed by less than 2% for the minimum block volume in the range 0.4-1.0 m3 and by 6-7% for larger blocks. On the other hand, measurements of discontinuity spacings that were taken on the basis of an orthophotomap can only serve to estimate the approximate maximum value of this parameter. However, the use of orthophotomaps gives a more explicit spatial pattern of the main vertical joint sets than direct measurements in the quarry.

The analysis results also showed the following: (i) the presence of tectonic disturbances visible at the highest level of the deposit; (ii) higher density of set A fractures with planes deepening in the NE direction and a considerable reduction of the QB parameter, particularly in the peripheral NE and SW parts of the deposit; (iii) differences in the orientation of the discontinuity system between particular beds. The variable density of the discontinuities in the excavation is related to the presence of the faults that limit the Górka-Mucharz deposit.

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Authors and Affiliations

Beata Figarska-Warchoł
ORCID: ORCID
Grażyna Stańczak
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Abstract

In the article there was described the current state of mines against a background of tradition of exploitation and application of rock raw materials. Active quarries were selected, where the extraction of rock blocks has been a tradition, as well as quarries where the geological structure of the deposit allows to exploit the blocks in the future. There were also assessed old quarries and their deposits where the popular stones had been extracted in the past and then used in domestic architecture as a decorative materials. That is a group of more than 230 deposits in total. It has been presented economically justified perspectives of exploitation development concerning decorative and architectural rocks in south-eastern Poland against a background of European market requirements, the state of resources and environmental limitations. It was established that they are differentiated depending on the decorative properties of the rocks, their block divisibility and quantity of resources. Taking above-mentioned into consideration the deposits have been classified to groups which have the chances of exploitation development in the European, domestic and local scale. The former are Zygmuntówka Conglomerate, Morawica Limestone, Zalesiaki Limestone and Diplopora Dolomite. The domestic scope of use can be associated with properly developed deposits of Paleozoic limestones in the vicinity of Kielce and Krzeszowice and some dimension sandstones in the margin of the Holy Cross Mountains and in the Carpathians. The small deposits of sandstones from the Holy Cross Mountains margin and from the Carpathians as well as deposits of limestones from the Kraków-Częstochowa Upland, excavating material used in so called small architecture, have guarantee of local development. Moreover there was shown the hazard to the dimension stones deposits connected with the huge consumption of their resources for the production of crushed aggregates. This problem concerns especially raw materials with good physico-mechanical properties. For the most attractive rocks it was justified the need of their protection against exploitation for the other purposes than block production. It was stated that the return to local masonry traditions is possible and necessary because of many connections with the national culture through its history, architecture and art. It requires large investments for modernize the exploitation methods as well as for promotion of Polish stones in the European market. It must be also taken into consideration the possibility of financial support from the European Union funds.

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Authors and Affiliations

Jan Bromowicz
Beata Figarska-Warchoł
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Abstract

The article presents and describes the methodology of the conservation of stone structures that are architectural monuments discovered as part of the work carried out during archaeological excavations in Tanais. The authors’ experiences presented in the article result from many years of cooperation between the Faculty of Civil Engineering at Warsaw University of Technology and the Antiquity of Southeastern Europe Research Centre at the University ofWarsaw. Examples of preserved masonry structures come from an excavation in Tanais near Rostov-on-Don. Works on stone structures located in the area of archaeological excavation are characterised by a unique specificity covering both formal issues, resulting from international standards and agreements regulating the conservation of historic buildings, as well as technical and environmental issues. The primary technical issues include ensuring the safety of further excavation works, protection of masonry structures against the destructive effects of atmospheric conditions and preparing the structure for possible exhibition in archaeological parks organized on the site of excavations. The article presents the procedures that should be used to conserve this type of structure and the specific sustainable technological and material solutions used in the shown objects.
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Authors and Affiliations

Wojciech Terlikowski
1
ORCID: ORCID
Ewa Sobczyńska
1
ORCID: ORCID
Martyna Gregoriou-Szczepaniak
1
ORCID: ORCID
Kacper Wasilewski
1
ORCID: ORCID

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

Steel slag stone can be used as a substitute for coarse aggregate in concrete. In this study, the performance of steel slag concrete (SSC) in the wall brick structure was analyzed. The specimens with a steel slag replacement rate of 0%, 20%, 25%, 30%, 35%, 40%, 45%, and 50% were designed, and the slump, stability, and carbonation resistance were tested. The results showed that the slump decreased with the increase of the replacement rate of steel slag stone. At the 60th min, the slump of SSC50 was 74 mm, which was 25.25% smaller than SSC00. When the replacement rate was more than 30%, cracks or fractures appeared, and the stability was destroyed. Twenty-eight days after the carbonation experiment, with the increase of the replacement rate, the carbonation resistance of the specimen decreased, and the performance was best when the replacement rate was 25%. The experimental results show that the performance of SSC is the best when the replacement rate of steel slag stone is 25%, which can be further promoted and applied in practice.
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Authors and Affiliations

Qing Su
1
ORCID: ORCID

  1. Wuchang University of Technology, No. 16, Jiangxia Avenue, Jiangxia District, Wuhan, China
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Abstract

Stone mastic asphalt is a gap-graded mix and is usually related to its high bitumen content and its skeleton-like constitution. Although famous for its durability, high resistance to fatigue and rutting, issues such as bleeding and premature aging do occur in the mix since it has a high bitumen content and voids due to its gap-graded structure. In order to encounter these problems from affecting the mix, some instances such as adding additives, rejuvenators and stabilizers into the mixture has been implemented. Nowadays, nano materials are being used in the asphalt mixtures and nano titanium is being introduced as a modifier to the asphalt binder in order to improve the mechanical properties of the stone mastic asphalt mix. The related tests done in order to access the improvement are resilient modulus, dynamic creep, moisture susceptibility and binder drain down. The content of nano titanium used in this research are 1%, 2%, 3%, 4% and 5%. This study is done to assess the mechanical performance of stone mastic asphalt with nano titanium modified binder.
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Authors and Affiliations

Nur Syafiqah Shamimi Mohd Zali
1
ORCID: ORCID
Khairil Azman Masri
1
ORCID: ORCID
Ramadhansyah Putra Jaya
1
ORCID: ORCID
Mohd Mustafa Al Bakri Abdullah
2
ORCID: ORCID
Muzamir Hasan
1
ORCID: ORCID
Mohd Rosli Mohd Hasan
3
ORCID: ORCID
Bartłomiej Jeż
4
ORCID: ORCID
Marcin Nabiałek
4
ORCID: ORCID
Marek Sroka
5
ORCID: ORCID
Paweł Pietrusiewicz
4
ORCID: ORCID

  1. Department of Civil Engineering, College of Engineering, Universiti Malaysia Pahang, 26300 Gambang, Kuantan, Pahang, Malaysia
  2. Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia
  3. School of Civil Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia
  4. Department of Physics, Faculty of Production Engineering and Materials Technology, Czestochowa University of Technology, 42-201 Czestochowa, Poland
  5. Division of Materials Processing Technology and Computer Techniques in Materials Science, Silesian 21 University of Technology, Poland
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Abstract

The physical properties determining the strength parameters of bituminous mixtures are strongly influenced by the processes of placement and compaction. The effectiveness of this process depends on the compactive effort and is directly related to the mixture temperature. This research focused on the assessment of compactibility of mixtures designed for reflective crack relief interlayers (RCRI) which, in most cases, are applied in thin layers. The materials analysed for compactibility in this research included AC – asphalt concrete, AC AF – asphalt concrete “anti-fatigue”, SMA – stone mastic asphalt and SMA-MA – stone mastic asphalt rich in bitumen mastic. The gyratory compactor method was used to determine the compaction slope K, the locking point LP and the compaction densification index CDI. All the tested mixtures were fine-graded, i.e., contained grains up to 8 mm in diameter, each mixed with a different type of bituminous binder. The values of CDI show a substantially greater input of energy required for compaction of high-polymer modified mixtures, as compared to mixtures of the same design, yet containing the 50/70 bitumen. Locking point analysis showed that SMA and SMA-MA mixtures attain 98% relative compaction before reaching the locking point at which the aggregate skeleton starts to resist further compaction. This is quite the opposite as with the AC and AC AF mixtures. Among the tested mixtures the best compaction behaviour was observed in the case of SMA-MA 8 50/70, and this over a wide range of working temperature (100–160C°) and pressures (150 kPa, 600 kPa). The design of the mixture SMA-MA as an anti-fatigue layer assumes an increase in the content of filler and binder, as compared to conventional SMA. This composition is bound to reduce the resistance to compaction, i.e., provide a better compaction behaviour as compared to a conventional SMA mixture.
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Authors and Affiliations

Oliwia Merska
1
ORCID: ORCID
Paweł Mieczkowski
1
ORCID: ORCID
Stanisław Majer
1
ORCID: ORCID

  1. West Pomeranian University of Technology, Faculty of Civil and Engineering, ul. Piastów 50A, 70-333 Szczecin, Poland
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Abstract

Natural stones are used as coating material on the exteriors and terraces of buildings in architecture, and in places such as entrances, halls, living rooms, kitchens, bathrooms and stairs in interior spaces. Limra limestone and travertine are used as natural building materials in many structures depending on their colors. However, the water absorption values of these two natural stones are high due to their porosity, resulting in negative effects from atmospheric conditions. In this study, two different carbonate-based natural stones, limra limestone and travertine, were treated with two different water-repellent chemicals, one solvent-based and one water-based. After application, thermal shock tests were performed with a sodium chloride solution consisting of twenty cycles. The changes in the weights of samples dried to constant mass, ultrasonic permeability, Leeb hardness, and color change values in the samples were determined after the thermal shock tests. In addition, the effects of water-repellent chemicals on the formation of NaCl crystals accumulated in the pores of the rocks were examined by SEM and EDX analysis. Changes in non-destructively measured values were compared with the values of reference samples without surface protection. The solvent- based water-repellent chemical made the sample surface more hydrophobic than the water-based repellent. In both types of natural stones, the solvent-based water repellent chemical showed more protective properties against salt crystallization under thermal shock conditions compared to the water-based repellent.
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Authors and Affiliations

Gökhan Ekincioğlu
1
ORCID: ORCID

  1. Kırşehir Ahi Evran University, Kaman Vocational School, Department of Mining and Mineral Extraction,Turkey
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Abstract

The study involved experimental work implemented from April 2014 until March 2017. Its purpose was to observe grape production quality parameters, such as yield, water productivity, berry size and bio-mass. Different irrigation methods, such as drip irrigation (DI), drip irrigation with plastic mulching (DIPM), drip irrigation with organic mulching (DIOM), subsur-face irrigation with stone column (SISC), subsurface irrigation with mud pot (SIMP), and subsurface irrigation with plastic bottles (SIPB) have been used during the experimental work. The crop has been irrigated following the CROPWAT-8.0 model developed by the FAO. Climate parameters are obtained from the automatic weather station located near the experi-mental field. Based on experimental results and analyses, it has been observed that the drip irrigation with the plastic mulching method is the best for irrigation in terms of the grape yield comparing with all other methods due to its highest productivity of 35–40%. Subsurface irrigation with the plastic bottle method is found to be suitable as it gives 20% higher yield than the traditional drip irrigation method. The SIPB method shows the cost-benefit ratio of 112.3, whereas the DIPM method had the ratio of 36.6. Based on the cost-benefit analysis, it is concluded that the SIPB method is economically more viable as compared with all other methods. Hence, based on the findings, it is recommended to use drip irrigation with a plastic mulch-ing and drip irrigation with a plastic bottle as the best options to achieve grape productivity while using minimum water.
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Authors and Affiliations

Sharad J. Kadbhane
1
ORCID: ORCID
Vivek L. Manekar
2
ORCID: ORCID

  1. Savitribai Phule Pune University, NDMVPS KBT College of Engineering, Nashik, Udoji Maratha Boarding Campus, 422013, Nashik, India
  2. Sardar Vallabhbhai National Institute of Technology, Surat, Gujarat, India
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Abstract

Stone arch bridge is an important type in the early bridge construction process because of its beautiful shape, material saving and economic rationality. However, stone material will deteriorate after long-term operation, which results in a decrease in strength and bearing capacity of stone arch bridge. The vehicle load is increasing at the same time. Therefore, accurate evaluation of bearing capacity of stone arch bridge is essential to ensure safety. In this article, a three-span open-spandrel stone arch bridge was taken as research object. Firstly, the bridge damages were investigated and analyzed in detail, and bridge service state was evaluated. Then, based on the evaluation results of disease damages and considering stone material deterioration, a refined finite element model of stone arch bridge was established to analyze bending moment, axial force, strain and deformation. Finally, static load test was carried out to test vertical deformation and stress of arch ring, horizontal displacement of pier, settlement of foundation and development of cracks. The results show that static load test is the most accurate method for evaluating bearing capacity of stone arch bridge. The evaluation accuracy of finite element model based on material correction is in the middle, and the evaluation accuracy of disease damage assessment is the worst. In practical work, bearing capacity of stone arch bridge can be evaluated by combining the three methods with high accuracy and comprehensive results.
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Authors and Affiliations

Hongshuai Gao
1
ORCID: ORCID
Hourui Duan
1
ORCID: ORCID
Yue Sun
1
ORCID: ORCID
Jiashuo Jian
1
ORCID: ORCID
Jingyuan Zhang
2
ORCID: ORCID
Hongbo Liu
1
ORCID: ORCID

  1. School of Civil Engineering, Heilongjiang University, Harbin 150080, PR China
  2. lnstitute of Engineering Mechanics, China Earthquake Administration, Harbin 150080, China
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Abstract

All over the world, highway traffic is increasing rapidly, as is the population and the road network. The country’s maximum and minimum temperatures also vary greatly. Moreover, the pavements are subjected to various types of damage. Pavement binders and mixtures are a constant area of research and development for scientists and engineers. Adding fibers to bituminous mixes may improve the properties of fatigue and strength of the material. Natural fibers may be used to improve asphalt mixtures performance due to their inherent compatibility with asphalt cement and excellent mechanical properties. Also, the high stone content and relatively high asphalt content in SMA mixture led to the occurrence of drain-down of the asphalt mastic from the mixture, and this problem requires the use of stabilizing additives such as cellulose fibers, mineral fibers, or polymers to mitigate this problem and ensure long-term performance. The most public sort of stabilizing additives is cellulose fiber. Overall, natural fibers in stone mastic asphalt mixes are discussed in this paper. An additional focus is on how asphalt concrete will be affected by natural fibers, mixing techniques, and managerial decisions. According to the review, the stabilizing and strengthening impact of natural fibers on the performance of asphalt mixes have been extensively researched. Natural fibers can significantly increase the rut and flow resistance of asphalt mixtures. Adding natural fibers to pavement can increase structural resistance to pavement distress.
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Authors and Affiliations

Israa AlSaadi
1
ORCID: ORCID
Sady A. Tayh
2
ORCID: ORCID
Abbas F. Jasim
2
ORCID: ORCID
Rana Yousif
2
ORCID: ORCID

  1. University of Baghdad, Department of Construction and Projects, Baghdad
  2. University, College of Engineering, Highways, and Transportation Engineering Department, Baghdad, Iraq
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Abstract

The dynamic replacement columns are formed by driving a coarse-grained material into a soft soil by means of repeatable drops of a pounder. The final shapes of the columns are non-cylindrical and depend on the subsoil conditions. This paper presents results of the laboratory study on influence of the thickness of the soft soil on the displacements of the backfill aggregate during the driving process. A test box with one acrylic-glass wall was prepared, in which, over a load-bearing sand layer, a soft soil of various thicknesses (���� = 0.3, 0.4 or 0.5 m) was modelled using a semi-transparent acrylic polymer. The displacements of the backfill gravel particles were tracked by means of a high-speed camera. The material was driven by dropping a 0.2 m high (����) pounder. The results revealed that the distance between the bottom of the first crater and the top of the sand layer played an important role in directing the particles. At ����/���� = 2.5 pear-shaped floating columns were formed as the grains in the side zones were less affected by the pounder drops and their paths deviated from the vertical axis by not more than 50°. In case of ����/���� = 2.0 and 1.5, the column bases reached the bearing layer and the impact energy caused much larger vertical and horizontal displacements of the backfill material in the side zones – the observed largest angles were equal to 64° and even 90°, respectively. Eventually, the final column shapes resembled a non-symmetrical barrel and a truncated cone.
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Authors and Affiliations

Sławomir Kwiecień
1
ORCID: ORCID
Siergey Ihnatov
1
ORCID: ORCID
Magdalena Kowalska
1
ORCID: ORCID

  1. Silesian University of Technology, Faculty of Civil Engineering, ul. Akademicka 5, 44-100 Gliwice, Poland
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Abstract

Large-scale stone-banked lobes and terraces are distributed over an area of 1 km2 of gentle slope on Rink Plateau in the northern part of James Ross Island, Antarctic Peninsula region. Topographically, there are two main features: relatively high risers up to 5 m high and distinct frontal ridges. In order to understand the processes responsible for these lobes and terraces, the authors have monitored air and ground temperatures and movement of stones on the surface over the period 1995-2005. In February 2005, the subsurface structures were surveyed by ground penetrating radar and drilling. The ground penetrating radar profiles identified the bedrock surface. The surface morphology of the lobes corresponds closely with that of the bedrock. The relatively high risers of these lobes are presumed to be due to a cessation of frontal advance.

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Authors and Affiliations

Junko Mori
Kotaro Fukui
Toshio Sone
Jorge A. Strelin
Cesar A. Torielli
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Abstract

Communication noise is classified as one of the pollutions for the current environment. Experimental techniques to measure tire-pavement noise generation from asphalt pavements in the laboratory have been limited. A series of experiments were conducted on six different asphalt mixtures to determine if Purdue University’s Tire-Pavement Test Apparatus (TPTA) could be used to overcome these limitations. The procedure produced samples with low tire-pavement noise; however, the air void contents of the samples were higher than designed. Despite these difficulties, the sample preparation technique and the TPTA testing protocol were shown to offer an effective approach for quick laboratory assessment of tire-pavement noise characteristics of hot mix asphalt pavements at a substantially reduced cost compared to field testing.

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Authors and Affiliations

K.J. Kowalski
T. Dare
R.S. Mcdaniel
J. Olek
R. Bernhard

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