Rubberized Concrete Research Articles

Experimental assessment and compressive constitutive model of rubberized concrete confined by steel tube

To investigate the confining effect and axial compressive behavior of rubberized concrete (RuC) confined by steel tube, axial compression tests were carried out on 12 circular RuC cylinders confined by steel tube. The cylinders considered parameters such as steel tube thicknesses (2 mm, 3 mm, 4 mm) and rubber volume replacement ratios of the fine aggregates (0%, 10%, 20%, and 30%). It was observed that the compressive strength of RuC decreases as the rubber volume replacement ratio increases. However, an increase in steel tube thickness enhances the confining effect of the core RuC, leading to an increase in its compressive strength and the corresponding strain, similar to that of conventional concrete. Moreover, post-peak curves are more likely to exhibit a strengthening part in confined concrete with more rubber content. Furthermore, a model was developed to determine the compressive strength of RuC confined by steel tube. Finally, an axial stress-strain model of steel tube confined RuC was proposed, which was validated against test results.

The Effect of Polypropylene Fibers on the Fracture Characteristics of Lightweight Aggregate Crumb Rubber Concrete Composites

The increasing use of rubber tires and their low recycling ratio have made them a serious environmental problem. This work aims to develop and investigate enhanced lightweight aggregate crumb rubber concrete (PFLWACRC) composites regarding the fracture properties of concrete. Polypropylene (PP) fibers are commonly familiar with increased crack growth endurance of concrete. On the other hand, the reuse of waste rubber in concrete plays a major role in the mitigation of the effects of climate change. Various concrete mixtures were designed with conventional Portland cement and common lightweight coarse aggregates. The variables considered in this study are PP fibers in different percentages (0.2%, 0.4%, and 0.6% volume fraction), and crumb rubber with various substitution proportions (0%, 5%, 10%, 15%, 20%, and 25% of fine aggregates). Cement with 450kg/m3 density with 10% silica fume was used. The fracture characteristics, which involve fracture toughness (KIC) and fracture energy generation (GF), of all concrete mixtures were evaluated by testing two types of samples, i.e. 54 notched concrete beams with dimensions of 10×10×52cm and 54 cylinders with diameter×height equal to 15×30cm. The results showed that the fracture toughness generation addresses the energy scattering limit of concrete mixtures. The findings showed that the existence of PP fibers increased the fracture energy and critical Crack Mouth Opening Displacement (CMOD)c. The PP fibers had a limited effect on the compressive strength and may even reduce it, but a remarkable enhancement of the energy absorption was observed.

Experimental investigation of durability properties of rubberized concrete

Experimental investigation of durability properties of rubberized concrete

Study of Mechanical Characteristics of Steel Tubular Sections Filled with High-Volume Rubberized Concrete

Study of Mechanical Characteristics of Steel Tubular Sections Filled with High-Volume Rubberized Concrete

Mechanical properties of blended-rubberized concrete

Recently, the disposal of waste tire rubber is no longer a non-common environmental problem, which is due to its non-biodegradable nature. Many works were done with regard to the utilization of crumb rubber from waste tires into concrete. In conjunction to deal with the disposal issues, this effort also preserving the natural sources of aggregate and producing a green sustainable concrete. In this study, the crumb rubber was used in the concrete containing metakaolin and it replaced fine aggregate content at 10% and 15%. The investigations were conducted on the mechanical properties of concrete like compressive strength, split tensile strength, flexural strength and elastic modulus. The result showed reduction in mechanical properties is proportionate with the increment of crumb rubber. The bond between cement paste and rubber particles was found to be a factor affecting its strength. The finding indicated that the strength of blended-rubberized concrete decreased about 13% with increasing crumb rubber content from 10% to 15%. Thus, the study concluded that there was no significant strength reduction for rubberized concrete with increasing crumb rubber content (up to 15%). Furthermore, the compressive strength was complied to the minimum requirement for building structural application (25MPa). Thus, the blended-rubberized concrete has promising potential properties for the construction applications.

Experimental Study on Rubberized Concrete using Zeolite and Geopolymer

Abstract: In Earth, as we know that there is a lot of minerals and ores are present. This is also containing soil and aggregates in it. Nowadays, as we know that there is depletion of concrete materials which is available now days. So, in this project we are going to create or making some concrete with some admixtures and partially replacing with some other materials and making an economical concrete and obtain the concrete which is giving us a good result also. In this project we are going to study the effects of rubberized concrete using zeolite and geopolymer and at the end we are going to compare the results with the normal concrete. In this we are also going to use an alkaline activator. With the help of this activator the geopolymers act as a Cementous material when this alkaline activator mix aur react with Industrial waste or natural material. As we had studied from the previous papers that with the help of rubberized concrete using zeolite and geopolymer which conclude that this type of concrete had a good binding property with iron bars and this concrete is not affects the reinforcement bars as compared to our normal concrete.

Mechanical Properties, Durability, and Structural Applications of Rubber Concrete: A State-of-the-Art-Review

Substituting rubber particles for a portion of the standard coarse aggregates in concrete is regarded as a sustainable solution for tackling the issue of waste-tires disposal. In order to assess the structural performance of rubber concrete (RC), many studies have been conducted on the proportions, mechanical properties, curing conditions, usages, and serviceability performance of the material over the decades. This review systematically summarizes the mechanical properties (e.g., static and dynamic), testing method, and durability of RC, emphasizing its dynamic characteristics from the perspectives of material and component. The inclusion of rubber particles weakens the static properties of the concrete, while the low module of inherent rubbers improves the concrete dynamic properties, such as low stiffness degradation, high strain-rate sensitivity, excellent energy dissipations, and good ductility. With the increase in the strain rate, the improvement in energy absorption and ductility of the RC (0 to 30%) can increase to 110% and 80%, respectively. Concrete with a rubber volume fraction of less than 30% enhances both mechanical and long-term environmental performances. Moreover, RC shows good fire resistance, permeability, and freeze–thaw behavior; however, further research is needed to understand its constitutive model and the synergistic effects of additional materials.

Durability Performance and Thermal Resistance of Structural Self-Compacting Concrete Improved with Waste Rubber and Silica Fume

Waste rubber takes many years to decompose, and thus the increasing number of tires in the world can be characterised as an important environmental issue, which generated the idea of implementing crumb rubber in structural self-compacting concrete (SCC). According to previous studies, up to 15% recycled rubber and 5% silica fume can be used to achieve the required properties of SCC in reinforced structural members with congested reinforcement, both in the fresh and hardened state. Most studies have focused on investigating the mechanical properties of self-compacting rubberised concrete (SCRC), and only a small number of studies investigated the durability and thermal properties, with contradictory findings. This study aims to determine the influence of crumb rubber and silica fume on the durability and thermal properties of SCC, with an emphasis on the selection of environmental exposure classes, the safety of using such a material in reinforced concrete members, and additional serviceability and durability requirements. This was further advanced by investigating the micro-structure of hardened SCC with recycled rubber and silica fume using a scanning electron microscope (SEM). Test results indicate that the combining effect of crumb rubber and silica fume has a positive impact on the thermal and durability properties of SCC.

Retracted: Non-Linear Analysis of Hybrid Reinforced T- Beam with Partial Substitution Recycled Rubberized Concrete

Abstract At present, the need to make use of industrial waste materials is increasing due to their harmful effects on the environment. In the present work, the behavior of hybrid reinforced T-Beam with partial substitution recycled rubberized concrete is studied. The finite element modeling by using ANSYS version 15 program. It contains also all the required steps needed to create the concrete models that were prepared to study the behavior of beams with partial substitution recycled rubberized concrete (RRC). The reinforcement of beams was various combinations of polymer GFRP and steel bars. The Rubberized concrete mixes were prepared by partial substitution 7.5 %, 10 %, and 12.5 % replacements by volume. The ratio of GFRP to steel reinforcement at mid‐span section was the second parameter investigated. Due to the large number of parameters affecting the behavior of Hybrid Reinforced T- Beam with partial substitution Recycled Rubberized Concrete, an extensive parametric study was performed using ANSYS version 15 program. Three parameters were investigated namely; Bottom RFT, compressive strength of concrete, and the existence of opening. The analytical results agree well with the experimental results in terms of mode of failure and the failure load values. The results indicated that although the flexural capacity of the tested specimen decreased with the addition of Crumb Rubber and reduced its self-weight. The failure load of the beam with partial substitution recycled rubberized concrete increases with bottom reinforcement by the GFRP bar or CFRP bar. Also, reinforced beams by CFRP bars had a higher failure load than reinforced beams by GFRP bars. Having an opening in hybrid reinforced T-Beam with partial substitution recycled rubberized concrete reduced the beam load capacity and maximum deflection. Also, using GFRP bars, and CFRP bars in the vicinity of openings in hybrid reinforced T-Beams increased the load capacity of these beams.

Sand Partial and Full Replacement in Concrete Composite with Rubber Crumbs

The objective of the research on rubberized concrete that substitutes sand fillers with rubber crumbs by volume or weight is to identify ways to utilize discarded rubber tires and improve the building industry’s sustainability. The research indicates that substituting sand fillers with rubber crumbs can have a substantial effect on the concrete’s physical and mechanical qualities. Significant decreases in flexural strength and compressive strength are observed when 100 % of the sand is replaced with rubber crumbs, showing that the attributes of rubber concrete are weaker than those of conventional concrete. Note that the precise mix design and proportion of rubber crumb replacement will alter the qualities of rubber concrete. Therefore, it is essential to conduct proper laboratory testing and trial mixing in order to optimize the mix design and determine the replacement % that would deliver the needed qualities and match the standards. The flexural strength of the reference sample was 2.7 MPa and its compressive strength was 57.7 MPa, compared to the compressive strength of the sample in which 100 % of the sand was replaced with rubber crumbs. The flexural strength of sr100 was 0.39 MPa and its compressive strength was 4.4 MPa. It is also important to note that rubberized concrete may still have some advantages over ordinary concrete, such as enhanced sound insulation, thermal insulation, and chloride ion penetration resistance. These characteristics may make it useful for applications including sound barriers, underground constructions, and marine structures.

Experimental Analysis and Evaluation of the Compressive Strength of Rubberized Concrete During Freeze–Thaw Cycles

Recycling scrap tires provides an alternative source of fine aggregates for the production of rubberized concrete and this will lead to significant increase in concrete frost resistance, environmental protection, and conservation of natural sand and gravel resources. In this paper, a total of 25 groups of rubberized concrete were produced by adding scrap tire rubber particles of different sizes, contents, and pretreatment methods to replace the fine aggregate, and their compressive strength during freeze–thaw cycles was studied from both the macro- and meso-perspectives. The results indicated that the decrease in concrete strength and weight was notably restricted by the presence of rubber particles during freeze–thaw cycles. The rubber fine aggregate with smaller particle sizes enhanced the concrete frost resistance more significantly, and the F100 of concrete with rubber particles of 1.0–2.0 mm increased from 76.6 to 86.5% by increasing the rubber content from 0.0 to 5.6%. The effects of rubber fine aggregate on concrete compressive strength during freeze–thaw cycles were quantified. On this basis, a forecast model for rubberized concrete compressive strength in freeze–thaw cycles was proposed, and the effects of the particle size, content, and pretreatment of the rubber particles were considered. The calculated results agreed well with the test results both in this study and the relevant peer studies, indicating that the model can provide a good reference for the design and engineering application of rubberized concrete in frigid environments.

Effect of graphene oxide on the microscopic, physical and mechanical characteristics of rubberized concrete

Effect of graphene oxide on the microscopic, physical and mechanical characteristics of rubberized concrete

Experimental and simulation study on capillary water absorption of modified crumb rubber concrete with steam-cured

It is well known that the process of steam curing will cause micro-cracks in concrete, which will adversely affect its water absorption performance. In this study, rubber particles were added into steam-cured concrete to reduce its water absorption capacity. Three types of rubber contents and two rubber modification methods, namely, NaOH modification and silane coupling agent (SCA) modification, were considered herein. Compressive strength, capillary water absorption (CWA), contact angle test of concrete was tested, and Fourier-transform infrared spectroscopy, Mercury intrusion porosimetry were used to study microscopic evolution, and ABAQUS simulations, molecular dynamics simulations were performed to reveal mechanism. The results showed that rubber particles could prevent the decrease in strength and reduce capillary water absorption coefficient in steam-cured concrete. When the rubber content was 70 kg/m3, the CWA coefficient of the steam-cured rubber concrete RC70-steam was reduced by 62.3% compared with that of the steam-cured concrete RC0-steam. Both NaOH and SCA modification introduce new functional groups on the surface of the rubber particles and reduce their contact angles, increased the water molecule content, endowing the surface with improved hydrophilicity, resulting in a more dense bond between rubber particles and concrete, thereby reducing the capillary water absorption coefficient. The addition of rubber particles optimised the pore structure inside the steam-cured concrete, and the proportion of transition pores was reduced by 5%, which contributed to improving the CWA of the concrete. The ABAQUS simulation showed that the addition of rubber increased the distortion effect of the water transport and extended the water transport path. The molecular dynamics results showed that the surface functional groups of rubber were changed and the hydrophobicity of rubber was reduced, which improved the bonding property of the rubber-concrete interface.

Study on mechanical properties and damage characteristics of rubber concrete under equal amplitude high stress repeated loading

Study on mechanical properties and damage characteristics of rubber concrete under equal amplitude high stress repeated loading

Experimental and numerical investigation on fracture characteristics of self-compacting concrete mixed with waste rubber particles

Replacing natural aggregates in concrete with waste rubber particles is an effective method to solve environmental problems, but the use of rubber due to its unknown characteristics can change the fracture performance and cracking behavior of self-compacting concrete. Hence, through experimental analysis and discrete element method (DEM) simulation, this paper aims to investigate the influence of different rubber contents (0%, 10%, 20% and 30%) on fracture characteristics of self-compacting concrete. Compared with natural river sand, rubber particles have more flexible structure and stronger deformation ability, and these unique properties enhance the bridging effect between matrices and weaken the stress concentration at the crack tip, which shows that the fracture parameters of self-compacting rubberized concrete (SCRC) increase linearly with the increase of rubber content, and this linear growth rate will increase with the increase of beam size. Moreover, the addition of rubber particles absorbs most of the energy generated in the fracture process, which significantly enhances the anti-cracking ability of SCRC, and this ability to prevent crack propagation will be enhanced with the increase of rubber content, which is manifested by the significant decrease of acoustic emission (AE) activity. Based on the shapes of real aggregates and rubber particles, a universal DEM fracture prediction model for SCRC is established, which can better describe the fracture response of SCRC with different rubber contents and sizes under flexural loads. The evaluation of economic and environmental benefits indicates that adding rubber particles into self-compacting concrete can not only save costs, but also produce considerable environmental benefits.

Rubberized Geopolymer Mortar and Concrete: A Comprehensive Review.

In many crucial structural applications, a material’s ability to withstand impact is of the utmost importance. The use of crumb rubber particles as a partial replacement of natural aggregates forms rubberized geopolymer concrete (RuGPC), which is found to have great impact resistance and energy absorption capacity. Geopolymer paste and natural aggregates alone are weak in handling the impact loads. The field of Civil engineering has been looking into ways for the last few years to use solid waste and ecologically friendly raw materials as components of concrete in building to embrace sustainability. Greenhouse gas emissions from cement manufacturing and the depletion of natural aggregates are two major issues the construction industry is currently experiencing. RuGPC, which combines the benefits of geopolymer concrete (GPC) and rubberized concrete to create a practical, sustainable building material, has been a hot topic for the past few years. In this paper, the fresh properties, strength and durability characteristics, mixing procedure and curing properties, dynamic and impact properties, microstructures and thermal properties of rubberized geopolymer mortar and concrete are comprehensively reviewed.

Experimental Study of Crack Characteristics of Self-Compacting Rubberized Concrete under Four-Point Bending Based on Acoustic Emission Technique

Experimental Study of Crack Characteristics of Self-Compacting Rubberized Concrete under Four-Point Bending Based on Acoustic Emission Technique

Numerical analysis of the thermomechanical behavior of rubber concrete at high temperatures

AbstractInsufficient research has been done on the mechanical and thermal properties of rubber concrete in the presence of fire. In this paper, we do detailed numerical modeling of the rubber concrete's thermomechanical behavior under dynamic conditions at high temperatures (800°C) using different percentages of rubber aggregate (0%, 10%, 20%, and 30%). The novelty of this work lies in its analysis of the temperature profiles over time in rubber concrete. This analysis is carried out using finite difference models developed with the MATLAB tool to predict thermomechanical parameters such as elastic modulus, thermal strain, tensile strength, and compressive strength. In addition, the dynamic behavior of the rubber concrete under impact loading was predicted, including stress and velocity change as a function of time at elevated temperatures. By the equations of motion and transient conduction, the mathematical model developed is based on density, thermal conductivity, heat capacity, and thermal expansion. The comparison between numerical and experimental results, and the analysis of the influence of the percentage of rubber aggregates on thermomechanical parameters, as well as the influence of temperature on the evolution of stress and velocity as a function of time, have shown the effectiveness of the mathematical and numerical model developed.

Waste Plastic and Rubber in Concrete and Cement Mortar: A Tertiary Literature Review

In recent years, the addition of plastic and rubber waste to construction materials has been widely studied by the research community. This great interest can mainly be attributed to the achievable potential environmental and economic benefits, mainly deriving from the reduction of incinerated or landfilled wastes and the decrease of used raw materials. Several reviews have been published on the addition of polymeric waste materials in concrete and cement mortar mixtures, discussing properties, environmental and cost implications. However, there are not available studies that organize and analyses the knowledge presented in this review. For the scope, in this paper we present a tertiary study of previous relevant review articles from peer-reviewed journals, with the aim to provide an overview of the state of the evidence related to this topic and to highlight the main critical aspects and open issues. The overview provides conclusions drawn from the 33 included reviews finding different open issues on the theme regarding environmental performance, cost savings and impacts on the supply chain as well as long term health problem related to the use of waste plastic and rubber in concrete and cement mortar. For each open issue further research proposals are also suggested.

Performance of Rubber Concrete Containing Polypropylene and Basalt Fibers under Coupled Sulfate Attack and Freeze-Thaw Conditions: An Experimental Evaluation.

Rubber concrete (RC) is a new type of concrete that is currently receiving a lot of attention, solving serious pollution problems by grinding waste tires into granules and adding them to concrete. However, rubber concrete has deficiencies in mechanics and durability, and has been reinforced by adding fibers in many studies. In this study, the mechanical and durability properties of rubber concrete with added polypropylene and basalt fibers (PBRC) were investigated in a series of experiments including apparent morphology, mass, static compressive and tensile tests, ultrasonic non-destructive testing, and scanning electron microscope (SEM) tests under coupled environments of sulfate attack and freeze-thaw. The results showed that the mass loss rate of RC and PBRC gradually increased with the number of freeze-thaw cycles, with more pits and cement paste peeling from the specimen surface. Moreover, the compressive and splitting tensile strengths of RC and PBRC groups exhibited distinct trends, with the former group showing a lower residual strength relative to the latter. The residual compressive strength of the RC group was only 69.4% after 160 freeze-thaw cycles in 5% MgSO4 solution. However, it is worth noting that the addition of too many fibers also had a negative effect on the strength of the rubber concrete. Additionally, the scanning electron microscopy (SEM) results indicated that the fibers restricted the formation of microcracks in the microstructure and curtailed the brittleness of the concrete. This study can provide a valuable reference for the application of environmentally friendly material fibers in recycled aggregate concrete.