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Number of results: 19
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Abstract

A study was undertaken to investigate the effects of crumb rubber on the strength and mechanical behaviour of Rubberized cement soil (RCS). In the present investigation, 26 groups of soil samples were prepared at five different percentages of crumb rubber content, four different percentages of cement content and two different finenesses of crumb rubber particle. Compressive strength tests were carried out at the curing age of 7 days, 14 days, 28 days and 90 days. The test results indicated that the inclusion of crumb rubber within cement soil leads to a decrease in the compressive strength and stiffness and improves the cement soil’s brittle behaviour to a more ductile one. A reduction of up to 31% in the compressive strength happened in the 20% crumb content group. The compressive strength increases with the increase in the cement content. And the enlargement of cement content is more efficient at low cement content.

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Authors and Affiliations

F.C. Wang
W. Song
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Abstract

The paper discusses the use of multiclustering statistical analysis in the assessment of domestic wastewater filtration effectiveness. Calculations included data collected over four months of experiments with using waste as filling material of vertical flow filters for domestic sewage treatment. The effectiveness of pollutants removal was analysed in case of me-chanically shredded waste in the form of PET flakes, PUR foam trims, shredded rubber tires and wadding. The organic compounds (CODcr, BOD5) removal, suspend solids, biogens (as NH4+, PO43– ions) and oxygen saturation changing com-pared with sand filling was analysed. Multiclustering statistical analysis allowed to divide pollutants removal efficiency of analysed materials into 3 clusters, depending on the hydraulic loading. The first group consisted in quality parameters of treated sewage: the highest reduction of BOD5 and NH4-N. It included the values of quality parameters and indicators for the filtrates obtained at the lowest hydraulic load from columns filled with 60 cm of rubber tires or sand. The second group comprised the results for fillings containing foam, PET and rubber tires (the other hydraulic loads).It featured the highest reduction of total suspended solids and PO43–. Removal of easily biodegradable organic compounds was at a similar level in both cluster groups. The filter filled with polyester waste (wadding), which was as effective as 30 cm layer of sand, and the filters filled with 60 cm of sand working at the highest hydraulic load. Third group showed the lowest values of parameters and indicators for analysed filtrates.

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Authors and Affiliations

Dawid Bedla
Ewa Dacewicz
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Abstract

In this study, rubber seed/shea butter oil was used to formulate core oil. The formulated core oil was characterised. D-optimal mixture design was used for multi response optimisation of the functional properties of rubber seed-shea butter coil oil. Desirable values for some responses might be obtained from a factor combination while for others responses not so desirable values. Through multiple response optimisations, a factor setting that gives the desirable values for all responses was obtained. The selected optimum mixture setting for the formulated core oil is 65.937% Rubber seed and 34.063% Shea butter oil at desirability of 0.924. Under the optimum condition the functional properties of the core oil was found to be 39.57KN/M2, 626.85KN/M2, 36.63KN/M2, 593.906KN/M2, 412.605 and 167.309s for Green Compressive Strength, Dry Compressive Strength, Green Tensile Strength, Dry Tensile Strength, Permeability and Collapsibility respectively. The optimum conditions were validated with less than 0.2% error. The functional properties of the formulated core oil was compared to the functional properties of linseed core oil. It was found that rubber seed-shea butter core oil can be used for producing cores suitable for Aluminium casting.

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Authors and Affiliations

O.S. Onyekwere
C. Odiakaose
K.A. Uyanga
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Abstract

The paper focuses on a nonlinear model to represent the mechanical behaviour of a mix coil spring – rubber used in the secondary suspension of passenger rail vehicles. The principle of the model relies on overlapping of the forces corresponding to three components – the elastic component, the viscous component and the dry friction component. The model has two sources on non-linearity, in the elastic force and the friction force, respectively. The main attributes of the model are made visible by its response to an imposed displacement-type harmonic excitation. The results thus obtained from the applications of numerical simulation show a series of basic properties of the model, namely the dependence on amplitude and the excitation frequency of the model response, as well as of its stiffness and damping.

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Authors and Affiliations

Mădălina Dumitriu
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Abstract

The present work investigated the properties of rubber vulcanizates containing different nanoparticles (Cloisite 20A and Cloisite Na+) and prepared using different sonication amplitudes. The results showed that a maximum improvement in tensile strength of more than 60% over the reference sample was obtained by the nanocomposites containing 2 wt.% Cloisite 20A and 1 wt.% Cloisite Na+ and mixed with a maximum amplitude of 270 µm. The modulus at 300% elongation increased by approximately 18% and 25% with the addition of 2 wt.% Cloisite 20A and 3 wt.% Cloisite Na+, respectively. The shape retention coefficient of rubber samples was not significantly affected by the mixing amplitude, while the values of the softness measured at the highest amplitude (270 µm) were higher compared to those of mixtures homogenized with lower amplitudes. The loading-unloading and loading-reloading processes showed similar trends for all tested nanocomposites. However, they increased with increasing levels of sample stretching but were not significantly affected by filler content at a given elongation. More energy was dissipated during the loading-unloading process than during the loading-reloading. SEM micrographs of rubber samples before and after cycling loading showed rough, stratified, and elongated morphologies. XRD results showed that elastomeric chains were intercalated in the MMT nanosheets, confirming the improvement of mechanical properties. The difference between the hydrophilic pristine nanoclay (Cloisite Na+) and organomodified MMT (Cloisite 20A) was also highlighted, while the peaks of the stretched rubber samples were smaller, regardless of the rubber composition, due most probably to the decrease of interlayer spacing.
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Authors and Affiliations

Anita Białkowska
1
Małgorzata Przybyłek
1
Marta Sola-Wdowska
1
Milan Masař
2
Mohamed Bakar
1
ORCID: ORCID

  1. University of Technology and Humanities in Radom, Faculty of Chemical Engineering and Commodity Science, Poland
  2. Tomaš Bata University in Zlin, Centre of Polymer Systems, Czech Republic
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Abstract

A huge amount of carbon black (40-60 phr) was commonly used as a reinforcing material in manufacturing of tires to improve the technical properties of pure rubber. Carbon black causes severe health hazard like skin cancer, respiratory problem due to its fly loss property. This study focusses on reducing the usage of carbon black by replacing it with minimal quantity of nanoclay to compensate the technical properties of rubber. Natural Rubber nanocomposite are fabricated using solution and mechanical mixing method in presence and absence of compatibilizer. Cure characteristics, wear test and mechanical properties were examined. NR nanocomposite with dual filler in presence of compatibilizer showed enhancement in torque values, mechanical and wear resistant property. Wear resistance, tensile strength and modulus of dual filler nanocomposite was increased by 66.7%, 91% and 85% when compared to pure NR. Hence NR nanocomposite with dual filler in presence of compatibilizer was found as a proving and possible nanocomposite for tire application.
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Bibliography

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Authors and Affiliations

M. Harikrishna Kumar
1
ORCID: ORCID
Shankar Subramaniam
1
Rajasekar Rathanasamy
1
ORCID: ORCID
Samir Kumar Pal
2
ORCID: ORCID
Sathish Kumar Palaniappan
2

  1. School of Building and Mechanical Sciences, Kongu Engineering College, Perundurai – 638060, Tamil Nadu State, India
  2. Department of Mining Engineering, Indian Institute of Technology, Kharagpur – 721302, West Bengal State, India
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Abstract

Designing touch-down bearings (TDB) for outer rotor flywheels operated under high vacuum conditions constitutes a challenging task. Due to their large diameters, conventional TDB cannot suited well, and a planetary design is applied, consisting of a number of small rolling elements distributed around the stator. Since the amplitude of the peak loads during a drop-down lies close to the static load rating of the bearings, it is expected that their service life can be increased by reducing the maximum forces. Therefore, this paper investigates the influence of elastomer rings around the outer rings in the TDB using simulations. For this purpose, the structure and the models used for contact force calculation in the ANEAS simulation software are presented, especially the modelling of the elastomers. Based on the requirements for a TDB in a flywheel application, three different elastomers (FKM, VMQ, EPDM) are selected for the investigation. The results of the simulations show that stiffness and the type of material strongly influence the maximum force. The best results are obtained using FKM, leading to a reduction of the force amplitude in a wide stiffness range.
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Bibliography

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Authors and Affiliations

Benedikt Schüßler
1
ORCID: ORCID
Timo Hopf
1
ORCID: ORCID
Stephan Rinderknecht
1
ORCID: ORCID

  1. Technical University of Darmstadt, Institute for Mechatronic Systems, Germany
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Abstract

Rubberized concrete is made up of scrap tyre rubbers where the fine aggregate is partially replaced by it, as the waste rubber is being a threat to the environment. It is estimated that only 4% of the waste tyre is used in the application of civil engineering and also there is shortage of fine aggregates. The primary objective of this study is to investigate the preliminary concrete properties of M25 and M30 concretes. The fine aggregate is replaced by pre-treated crumb rubber with 10, 15 and 20 % of total weight. Various tests are conducted on the rubberized concrete specimens such as compressive strength, split tensile strength, flexural strength and slump test. The investigation is carried out to determine the impact load behavior of hybrid rubberized composite slabs. In addition 0%, 1%, 1.5%, and 2% of replacement of rubber fibers for total weight of coarse aggregate is also made. The specimen of size 300 mm x 300 mm x 50 mm thickness is subjected to drop hammer test to find its performance against the impact loads. The number of blows for the first crack and complete failure of slab was found and the characteristics were studied.

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Authors and Affiliations

P. Subashree
R. Thenmozhi
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Abstract

The wet flashover voltage of medium voltage insulators made of a silicone rubber is 8% lower than the wet flashover voltage of a porcelain insulator with an identical profile. These surprising results, obtained in 2012, were confirmed again in 2019. The flashover development on the composite insulator is very short (less than 30 ms). On the other hand, on the porcelain insulator, the flashover develops longer (1–3 seconds). The Koppelmann equation was modified, and the Obenaus model to calculate the flashover voltage of insulators under the artificial rain was presented. Attention was paid to the importance of insulator diameters and the phenomenon of water cascades.
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Bibliography

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Authors and Affiliations

Krystian Leonard Chrzan
1
Henryk Marek Brzeziński
2

  1. Wroclaw University of Technology, Poland
  2. Łukasiewicz Research Network – Institute of Electrical Engineering, Poland
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Abstract

Sand molding casting has been widely used for a long time. But, one of its main drawbacks is that surface quality of the castings is not good enough for some applications. The purposes of this research were to investigate the effect of addition of sawdust ash of rubber wood (SARW) on molding sand properties and the surface quality of iron castings and to find an appropriate level of SARW with the appropriate properties of the iron castings. The molding sand compositions for making a sand mold consisted of the recycled molding sand, bentonite, water and SARW. The percentage levels of SARW were 0%, 0.1%, 0.2%, 0.3% and 0.4%. The different proportions of molding sand samples were investigated for the molding sand properties including permeability, compression strength and hardness. The results showed that addition of SARW had an effect on the molding sand properties. The appropriate percentage proportion of molding sand was obtained at 95.8% recycled molding sand, 0.8% bentonite, 3% water and 0.4% SARW. There were statistically significant differences of mean surface roughness and hardness values of the iron castings made from molding sand samples without SARW addition and the appropriate percentage proportion of molding sand. In addition, the average surface roughness value of the iron castings made from the sand mold with the appropriate percentage proportion of molding sand was ~40% lower than those of the iron castings made from molding sand samples without SARW addition.
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Authors and Affiliations

R. Khuengpukheiw
1
S. Veerapadungphol
1
V. Kunla
1
C. Saikaew
1
ORCID: ORCID

  1. Department of Industrial Engineering, Khon Kaen University, Khon Kaen 40002 Thailand
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Abstract

Road construction relies on natural material exploitation and it is necessary to find new ways of reducing its negative environmental impact. Simultaneously, number of tyres placed on Croatian (and world) market is constantly growing and the need for waste tyres management will begin to increase due to the wear and tear of tyres in use at the moment. This paper presents a review of latest international and domestic researches on waste rubber application in road construction with special emphasize on Croatian researches within this topic. Preliminary results of ongoing research on waste rubber application in cement bound mixtures are also presented.
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Authors and Affiliations

Ivana Barišić
1
Matija Zvonarić
1
Ivanka Netinger Grubeša
2
Sanja Šurdonja
3

  1. Department for Geotechnics, Road Construction and Geodesy, Faculty of Civil Engineering and Architecture Osijek, University of Osijek, Vladimira Preloga 3, Osijek, Croatia
  2. Department for Materials and Constructions, Faculty of Civil Engineering and Architecture Osijek, University of Osijek, Vladimira Preloga 3, Osijek, Croatia
  3. University of Rijeka, Faculty of Civil Engineering, Croatia
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Abstract

Low calcium fly ash is used as the main material in the mixture and the crumb rubber was used in replacing fine aggregates in geopolymer mortar. Sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) which were high alkaline solution were incorporated as the alkaline solution. The fly ash reacted with the alkaline solution forming alumino-silicate gel that binds the aggregate to produce a geopolymer mortar. The loading of crumb rubber in the fly ash based geopolymer mortar was set at 0% (CRGM-0), 5% (CRGM-5), 10% (CRGM-10), 15% (CRGM-15), and 20% (CRGM-20), respectively. NaOH solution (12M) and Na2SiO3 solution ratio is set constant at 2.5 for all geopolymer mixture and the fly ash to alkali activator ratio was kept at 2.0. The CRGM at 28 days of curing time was exposed to elevated temperature at 200°C, 400°C, 600°C and 800°C. The weight loss of the CRGM increases with increasing temperature at all elevated temperatures. However, the density and compressive strength of CRGM decrease with an increase of crumb rubber loading for all elevated temperature exposure. The compressive strength of CRGM reduced due to the fact that rubber decomposes between 200°C and 600°C thereby creating voids. CRGM-15 and CRGM-20 showed cracks developed with rough surface at 800°C. Image obtained from scanning electron microscope (SEM) showed that, the CRGM changed significantly due to the decomposition of crumb rubber and evaporation of the free water at 400°C, 600°C and 800°C.
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Authors and Affiliations

Ahmad Azrem Azmi
1
ORCID: ORCID
Mohd Mustafa Al Bakri Abdullah
2
ORCID: ORCID
Che Mohd Ruzaidi Ghazali
3
ORCID: ORCID
Romisuhani Ahmad
4
ORCID: ORCID
Ramadhansyah Putra Jaya
4
ORCID: ORCID
Shayfull Zamree Abd Rahim
4
ORCID: ORCID
Mohammad A. Almadani
5
ORCID: ORCID
Jerzy J. Wysłocki
6
ORCID: ORCID
Agata Śliwa
7
ORCID: ORCID
Andre Victor Sandu
8
ORCID: ORCID

  1. Center of Excellence Geopolymer and Green Technology, University Malaysia Perlis (UniMAP), 01000, Kangar, Perlis, Malaysia
  2. Faculty of Chemical Engineering Technology, University Malaysia Perlis (UniMAP), 01000, Kangar, Perlis, Malaysia
  3. Faculty of Ocean Engineering Technology and Informatics, University Malaysia Terengganu, Terengganu, Malaysia
  4. Faculty of Mechanical Engineering Technology, University Malaysia Perlis (UniMAP), 02600, Arau, Perlis, Malaysia
  5. Department of Civil Engineering, Faculty of Engineering – Rabigh Branch, King Abdulaziz University, 21589 Jeddah, Saudi Arabia
  6. Department of Physics, Czestochowa University of Technology, 42-200, Czestochowa, Poland
  7. Division of Materials Processing Technology and Computer Techniques in Materials Science, Silesian University of Technology, 44-100 Gliwice, Poland
  8. Faculty of Material Science and Engineering, Gheorghe Asachi Technical University of Iasi, 41 D. Mangeron St., 700050 Iasi, Romania
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Abstract

Improper disposal of waste tires will not only bring environmental impact and safety risks but also cause a serious waste of resources. In the field of civil engineering materials, waste tire particles are used as a substitute for non-renewable aggregates to produce flexible rubber-cement composites (RCC). To explore the high-speed slicing stability of RCC, this test took normal cement mortar (NCM) and rubber cement mortar (RCM) as research objects. The SHPB tests with the same impact energy level and the high-speed slicing tests with a slice thickness range of about 1.4 mm ~ 4.4 mm were carried out. The results showed that NCM and RCM showed different stability differences in the process of high-speed slicing. In the case of ensuring the integrity of the slice, the minimum thickness of the slice can be better decreased with the increase of the rubber content. Finally, from the perspectives of split Hopkinson pressure bar (SHPB) test results and mesoscopic structure states, the essential reason for ensuring the stability of high-speed slicing lied in the improvement of rubber particles (dominant role) and pores on material deformation and flexible energy dissipation.
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Authors and Affiliations

Rongzhou Yang
1
ORCID: ORCID
Ying Xu
1
ORCID: ORCID
Pei Yuan Chen
2
ORCID: ORCID

  1. State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines, School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan 232001, China
  2. School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan 232001, China
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Abstract

Concrete-filled hollow steel (CFHS) has become more popular due to its advantages and benefits compared to reinforced concrete. This paper presents the experimental investigation on the performance of rubberized pozzolanic concrete-filled hollowsteel column (RuPCFHS) under monotonic and cyclic lateral load in comparison to bare hollow steel column and normal concrete-filled hollow steel column (NCFHS). The test parameters included the type of concrete infill and the level of axial load. Modified rubberized pozzolanic concrete with comparable compressive strength to that of normal concrete was used. Two types of axial load conditions: no axial load and 20% axial load were considered in the testing. The test results indicate that the performance of the columns improved when concrete infill was introduced in the hollow steel. The application of axial loading also increased the capacity of the column specimens. RuPCFHS behaved with comparable performance with NCFHS in both monotonic and cyclic testing. RuPCFHS recorded the highest increment in the energy dissipation capability when 20% axial load was applied to the column when compared to the other specimens. The comparable performance indicated the possibility ofRuPC as an infill material of CFHS andRuPCFHS as a structural component.
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Authors and Affiliations

Muhammad Najmi Mohamad Ali Mastor
1
ORCID: ORCID
Mariyana Aida Ab Kadir
2 3
ORCID: ORCID
Nurizaty Zuhan
2
ORCID: ORCID
Kasali Adebayo Mujedu
1
ORCID: ORCID
Mohd Zamri Ramli
4
ORCID: ORCID
Ramadhansyah Putra Jaya
5
ORCID: ORCID
Norhazilan Md Noor
2
ORCID: ORCID
Mohamad Syazwan Ahmad Shah
2
ORCID: ORCID

  1. Candidate, School of Civil Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor Bahru, Johor, Malaysia
  2. School of Civil Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor Bahru, Johor, Malaysia
  3. Institute of Noise and Vibration, Universiti Teknologi Malaysia, 81310 Skudai, Johor Bahru, Johor, Malaysia
  4. Candidate, School of Civil Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor Bahru, Johor,Malaysia
  5. Faculty of Civil Engineering Technology, Universiti Malaysia Pahang, 26300 Gambang, Kuantan, Pahang, Malaysia
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Abstract

Microwave curing of bamboo fiber increases the physical and mechanical qualities of cement concrete, according to previous studies. However, there are limited research on their endurance when used as an additive in concrete manufacturing to increase strength. The impact of bamboo fiber and Styrene Butadiene Rubber (SBR) on the mechanical and microstructure of the resulting concrete is investigated in this study. With the inclusion of bamboo fiber ranging from 0–1.5%, a mix ratio of 1:1.5:3 was used. To make the samples, 10% SBR by weight of cement was dissolved in the mixing water. The batching was done by weight, with a water cement ratio of 0.6. Compressive strength, water absorption, swelling, modulus of elasticity, and modulus of rupture were all studied as mechanical properties. Various characterization tests such as SEM, EDS, FTIR, XRD, and TGA were performed on the microstructure, crystalline nature, and mineral composition of certain samples. According to the FTIR study’s findings, peak levels were detected in the O–H stretching, C–H fiber and CH2 functional groups, carbonyl group, C–O and C–C functional groups. As the temperature climbed, TGA measurements showed a drop in weight. The XRD test revealed peak levels of 6.611, 4.255, and 3.855 for sanidine, quartz, and calcite, respectively. After 28 days, the inclusion of bamboo fibers as an additive in concrete shows some promising outcomes in compressive strength, with samples containing 1% and 1.5% bamboo fiber cured at 80°C having a higher compressive strength value.
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Authors and Affiliations

Ajayi Joseph Adeniyi
1
ORCID: ORCID
James Gana
1
ORCID: ORCID
Ariyo Adanikin
ORCID: ORCID
Kola Ogedengbe
1
ORCID: ORCID
Abundance Idowu
1
ORCID: ORCID

  1. Landmark University, School of Engineering, Department of Civil Engineering, Omu-Aran, Kwara State, Nigeria
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Abstract

Construction is one of the industrial sectors responsible for the use of large quantities of natural raw materials. This fact makes it necessary to look for new technologies of producing construction materials based as much as possible on waste materials. Such a solution could have positive effects on the environment and reduce construction costs. This paper presents the results of a study on the deformability of a mix made from anthropogenic waste combined with a hydraulic binder. The presented mixes consist of unburnt coal mining slates (mine waste), shredded rubber waste, silica fly ash and CEM I 42.5 R cement. Samples with two different contents of shredded rubber waste 0% and 10% were made from the mixtures and subjected to destructive compressive strength testing. The strength testwas combined with sample deformation measurement performed with the Aramis 3D Video Correlation System. The results presented show the effect of the shredded rubber waste content on the deformability of the sample.
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Authors and Affiliations

Konrad Walotek
1
ORCID: ORCID
Joanna Bzówka
1
ORCID: ORCID
Adrian Ciołczyk
1
ORCID: ORCID

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

The normal mode solution for the form function and target strength (TS) of a solid-filled spherical shell is derived. The calculation results of the spherical shell’s acoustic TS are in good agreement with the results of the finite element method (FEM). Based on these normal mode solutions, the influences of parameters such as the material, radius, and thickness of the inner and outer shells on the TS of a solid-filled spherical shell are analyzed. An underwater spherical shell scatterer is designed, which uses room temperature vulcanized (RTV) silicone rubber as a solid filling material and does not contain a suspension structure inside. The scatterer has a good TS enhancement effect.
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Authors and Affiliations

Bing Jia
1 2
Jun Fan
1
Gui-Juan Li
2
Bin Wang
1
ORCID: ORCID
Yun-Fei Chen
2

  1. Key Laboratory of Marine Intelligent Equipment and System Ministry of Education Shanghai Jiao Tong University
  2. Science and Technology on Underwater Test and Control Laboratory Dalian, Liaoning, China
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Abstract

The aging of composite insulators in outdoor operation for a long time has a direct impact on the safe and stable operation of the power grid. To solve this problem, fuzzy comprehensive evaluation of composite insulators based on level difference maximum is proposed. To verify the feasibility of this method, insulators in Xinjiang are sampled and the index evaluation system for composite insulators is established based on electrical, mechanical, hydrophobic and other properties, combined with operational years, geographical environment and other factors; Firstly, different membership functions are established according to index types. It is more likely to determine the grade of insulator by comparing measured data with the boundary value. Then, to solve the problem that weights cannot be effectively integrated in the combination weighting, level difference maximization is proposed (during the operation of insulators, the index which has a greater influence on the performance of insulators takes a higher proportion of the weight). Finally, on the basis of fully considering the clarity and ambiguity of grade division, the grade state of insulators is obtained by using the linear weighting method. The results show that compared with the traditional method, the improved method of the membership function and level difference maximum can realize the dynamic adjustment of the index based on the degree of information change. The method can better evaluate the insulator grade. The case study shows that the model can accurately and quickly judge the state of composite insulators, which can be used as a reference for manufacturing and maintenance departments.
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Authors and Affiliations

Sihua Wang
1
ORCID: ORCID
Long Chen
1
ORCID: ORCID
Lei Zhao
1
Junjun Wang
1

  1. Lanzhou Jiaotong University, Lanzhou, 730070, China
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Abstract

To promote the application of rubber-cement composites as the main bearing structure and key components in practical engineering under frequent dynamic disturbances, in this work, the split Hopkinson pressure bar (SHPB) cyclic impact tests of rubber-cement composite specimens with four different confine modes were carried out in which the impact load increased sequentially. The relationship between average strain rate, ultimate strain and impact times and the relationship between peak stress, damage energy, ultimate strain and incident energy were analyzed. The results showed that the appropriate confine reinforcement treatment can make rubber-cement composite give full play to its deformation ability when it was completely damaged. Carbon fiber-reinforced polymer (CFRP) sheet and steel cylinder can work together with the rubber-cement composite matrix to resist impact load, which effectively improves the structural strength, damage fracture energy, and cyclic impact resistance of the rubber-cement composite. Finally, based on the effect difference of confine modes, the simplified plane force models of rubber-cement composite specimens with four different confine modes were established, which clearly revealed the completely different impact resistance mechanism of the rubber-cement composites with different constraints under cyclic impact loading.
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Authors and Affiliations

Rongzhou Yang
1
ORCID: ORCID
Ying Xu
1
ORCID: ORCID
Peiyuan Chen
2
ORCID: ORCID
Lin Cheng
2
ORCID: ORCID
Jinfu Ding
2
ORCID: ORCID
Hongxin Fu
2
ORCID: ORCID

  1. State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines, School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan 232001, China
  2. School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan 232001, China

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