Scrap Tire Rubber Research Articles

Characterization of high-strength concrete by Preferential supplant of scrap tyre rubber powder-bambara nut shell ash constituent: utilization of novel waste materials in concrete

Characterization of high-strength concrete by Preferential supplant of scrap tyre rubber powder-bambara nut shell ash constituent: utilization of novel waste materials in concrete

Performance assessment of buildings seismically isolated with scrap tire rubber pad isolators

Performance assessment of buildings seismically isolated with scrap tire rubber pad isolators

Seismic vulnerability assessment of masonry building supported by STRP isolators

Scrap tire rubber pad (STRP) isolators are made from scrap automobile tires, which are expected to be a low-cost material for earthquake-resistant design of low-to-medium-rise buildings in developing countries. This paper describes the seismic vulnerability of a unbonded STRP (U-STRP) base-isolated masonry building using the finite element method. The three-dimensional model of the U-STRP isolators is placed between the foundation and the building without any bonding between them. As a result, the inertia force of the building is transferred to the foundation through the friction. Two alternative versions of the U-STRP isolator: strip-shaped and square-shaped, are analyzed, which have comparable geometric and stiffness properties. The fidelity of the U-STRP isolator model is confirmed using the numerical analysis and experimental results. The seismic vulnerability of the masonry base-isolated building is determined using the pushover analysis and the fragility curves and then compared to that of the identical fixed-base building. The findings show that masonry buildings with uniformly distributed square-shaped U-STRP isolators suffer low damage and base shear compared to those of the same size of strip-shaped U-STRP isolators. The U-STRP base-isolated masonry building has superior seismic performance to that of an identical fixed-base building, and a square-shaped U-STRP is more effective than the strip-shaped isolator.

Overview of Concrete Performance Made with Waste Rubber Tires: A Step toward Sustainable Concrete.

Utilizing scrap tire rubber by incorporating it into concrete is a valuable option. Many researchers are interested in using rubber tire waste in concrete. The possible uses of rubber tires in concrete, however, are dispersed and unclear. Therefore, a compressive analysis is necessary to identify the benefits and drawbacks of rubber tires for concrete performance. For examination, the important areas of concrete freshness, durability, and strength properties were considered. Additionally, several treatments and a microstructure investigation were included. Although it has much promise, there are certain obstacles that prevent it from being used as an aggregate in large numbers, such as the rubber’s weak structural strength and poor binding performance with the cement matrix. Rubber, however, exhibits mechanical strength comparable to reference concrete up to 20%. The evaluation also emphasizes the need for new research to advance rubberized concrete for future generations.

Performance evaluation of eco-friendly scrap tyre base isolation technology in distinct construction quality RC framed buildings located in seismic risk zone

The present investigation interprets the seismic and cost performance of scrap tyre rubber pad (STRP) bearings obtained from used automobile tyres to be installed in a developing country of a high seismic risk zone. As a consequence, Meghalaya, a state from India is selected for the research. The buildings vary in its construction quality such as poor, moderate and good construction and varying in storey heights such as three and five stories. Nonlinear analysis and cost-analysis of the buildings with and without STRP bearings are performed. The nonlinear modal time history analysis/fast nonlinear analysis is performed using SAP 2000 software and SeismoMatch software to check for convergence of the selected accelerograms with target spectrum. The dynamic response such as base shear, acceleration, storey drift and displacement are discussed and compared. The study exemplifies that the base shear reduction is superior in good construction type buildings compared to poor construction type. Moderate construction type buildings report good acceleration response, storey drift and displacement response compared to poor and good construction type. Substantially, it is reported that there is a significant reduction in cost with the implementation of STRP bearings of about 12% to 25% which is a promising one.

Impact of Crumb Rubber on Stabilization of Soils

The quantity of waste tires, an undesirable surplus, has been growing each year. The probabilities to take away scrap rubber tires to utilize these as a soil stabilizer, which increases the bearing strength of soil and also improved the bearing capacity of the soil. Trouble related to the socio-financial improvement of a rustic is waste tire decomposition. It has been a hard job to dispose of waste rubber tires safely. In this work, the opportunity of the usage of powder form of rubber tires as a supplement to enhance the shear strength of soft soil became evaluated. The bearing capacity of stabilized soils had been an advanced way of means of growing chances of crumb rubber. Besides this improvement, the effects of this kind of stabilizer and its distinctive portions on effluent traits also are analyzed. The addition of processed waste tires which are powdered form in each soil suggests acceptable adjustments in permeability. This research paper affords the improvement of soils the usage of fragmented waste tires at various proportions. The compressibility and unconfined compression strength of soil had been made used to measure the conduct & overall execution of the improved soils. Along with the test carried out with the soil Specimen, it became found, the highest dry unit weight and most efficient water content, material lower together with a boom in the proportion of stabilizer on soils. The value of shear strength increased with an increase in the proportion of mixtures and the highest values had been found at percentages of 5% & 15% for the specimens, S-1& S-2 severally.

A STUDY ON UTILIZATION OF WASTE MATERIALS AND ECO-FRIENDLY CONSTRUCTION MATERIALS TO MAKE GREEN CONCRETE

Conventional concrete is responsible for amount of carbon-dioxide emission to some Extend. So to reduce the emission of carbon-dioxide, various types of concrete are developed using waste products from industries use like fly ash ,silica fume cause least harm on environment. Materials are the essential components of buildings construction. Tyre is rubber member that provides cushion against the shocks and support load. Tyre is waste materials which cause many environmental effects in all the parts of the world representing very serious threat to ecology. One of the possible solutions for the use of scrap tyre rubber is to incorporate it into concrete, to replace some of the natural aggregate. Fly ash is a by-product at thermal power stations. An industrial by-product may be inferior to traditional materials used construction applications, but, the lower cost of these inferior materials makes it an attractive alternative if adequate performance can be achieved. The use of fly ash is accepted worldwide due to saving in cement, consuming industrial waste and making durable or workable materials, especially due to improvement in the quality fly ash products. Keywords — Green Concrete, Cement, flyash, tyres, coarse aggregate, fine aggregate & Word software 2007

Mechanical behaviour and permeability of expansive soils mixed with scrap tire rubbers subjected to freeze-thaw cycles

Due to the extensive generation of scrap tires around the world, the application of such waste materials has been considered as an environmentally friendly and cost-effective solution. In geotechnical and geo-environmental engineering, sub-productions derived from scrap tires have been effectively reused to modify the problematic expansive soils. However, no further evaluation has been explored on its performance under freeze-thaw weathering. To fill this gap, this paper presents an attempt to investigate the effect of freeze-thaw cycles on volume change, mechanical behaviour and permeability of expansive soils mixed with scrap tire rubbers. Scrap tire rubber in the form of crumb rubber powder was mixed with natural expansive soils with the percent by weight of 0%, 1%, 3%, 6%, 10%, 15% and 25%. All the laboratory tests were performed on expansive soil-rubber mixtures after 0, 1, 2, 3, 6, 10 and 15 freeze-thaw cycles. The volume change, stress-strain response, unconfined compression strength, resilient modulus, strain at failure as well as permeability coefficient of the expansive soil-rubber mixtures have been discussed. The results show that cyclic freeze-thaw has a significant degradation of mechanical and hydraulic performance of expansive soil-rubber mixtures. Small amount of rubber addition (CR = 1– 3%) will make soil less sensitive to swelling-shrinkage, thereby increasing strength/stiffness and reducing permeability. Under freeze-thaw weathering, CR = 10% plays a critical role in the transformation behaviours of stress-strain response, failure pattern and ductility with rubber content. Besides, independent of freeze-thaw cycles, the relations between resilient modulus and unconfined compression strength can be well expressed by a quadratic function. Increasing freeze-thaw cycles significantly increases the void ratio of parent soil matrix, thus leading to the increase in permeability. Additional research is encouraged to explore an effective method to prevent the freeze-thaw triggered performance deterioration of rubber modified expansive soils in practical projects.

Thermal conductivity of scrap tire rubber-sand composite as insulating material: Experimental investigation and predictive modeling

Scrap tire rubber of good thermal insulating properties can be reused with soils as a new sustainable construction material. While the heat conduction mechanism of this tire rubber-soil composite has not been fully understood. The present study investigated the thermal behavior of scrap tire rubber-sand composite for using it as an insulating material in thermo-active applications. Several series of thermal conductivity tests were conducted on scrap tire rubber-sand composite prepared with different sand/shredded tire particle size ratios, shredded tire mixing ratios, and degrees of saturation. A predictive model was developed within the framework of normalized thermal conductivity concept that could capture the experimental data. The results showed that addition of shredded tires leads to a considerable reduction in thermal conductivity of sand, indicating great potential of using recycled scrap rubber tires in the construction of insulation layers. With an increase in degree of saturation, the order of thermal conductivity increase was found to be: sand > scrap tire rubber-sand composite > shredded tires. The spatial distribution of solid particles changed from ‘rubber-connected insulation layer’ to ‘sand-encompassed conduction path’ with increasing sand/shreds tire particle size ratio. The normalized thermal conductivity exhibited a linearly increasing trend with shredded tire mixing ratio, and the increase rate mainly depended on degree of saturation and particle size ratio. The predicted thermal conductivity showed satisfactory accuracy for engineering design, as reflected by the absolute percentage difference being controlled under 25%. The validity of the prediction model was also demonstrated based on the experimental results reported in the published literature. Additional research is recommended to assess the effects of particle morphology on thermal conduction of the binary-solid particle system.

Waste-Tire-Derived Activated Carbon as Efficient Adsorbent of P-Nitrophenol from Wastewater

In this work, a two-stage activation method was used to prepare adsorbents from scrap tire rubber. Firstly, KOH was mixed with rubber using different impregnation ratios (1–2) for primary activation; a second activation was performed after pyrolysis at 650°C and 750°C; and finally, the samples were acid-washed using HNO3. The prepared materials were characterized by elemental analysis, nitrogen adsorption isotherms, SEM, FTIR, and XPS. The adsorption capacity and mechanism of these materials on p-nitrophenol in wastewater were also investigated. It was found that after two-stage activation, the specific surface area of the materials can be effectively increased, and the surface of the materials can be enriched with oxygen-containing functional groups. The maximum adsorption capacity of PNP could reach 143.9 mg g−1, which is slightly higher than the literature data under the same conditions. The adsorption process is in the form of chemisorption and is dominated by hydrogen bonding and π-πEDA formation, but the adsorption tends to be monolayer, and the adsorption behavior can be described by a proposed secondary model. In addition, the adsorbent has a stronger adsorption capacity under acidic conditions.

Asphalt Mixture with Scrap Tire Rubber and Nylon Fiber from Waste Tires: Laboratory Performance and Preliminary M-E Design Analysis

Scrap tire rubber and nylon fiber are waste materials that could potentially be recycled and used to improve the mechanical properties of asphalt pavement. The objective of this research was to investigate the properties of scrap tire rubber and nylon fiber (R-F) modified warm mix asphalt mixture (WMA). The high-temperature performance was estimated by the Hamburg wheel-tracking testing (HWTT) device. The low-temperature cracking performance was evaluated by the disk-shaped compact tension (DCT) test and the indirect tensile strength (IDT) test. The stress and strain relationship was assessed by the dynamic modulus test at various temperatures and frequencies. The extracted asphalt binder was evaluated by the dynamic shear rheometer (DSR). Pavement distresses were predicted by pavement mechanistic-empirical (M-E) analysis. The test results showed that: (1) The R-F modified WMA had better high-temperature rutting performance. The dynamic modulus of conventional hot mix asphalt mixture (HMA) was 21.8%~103% lower than R-F modified WMA at high temperatures. The wheel passes and stripping point of R-F modified WMA were 2.17 and 5.8 times higher than those of conventional HMA, respectively. Moreover, the R-F modified warm mix asphalt had a higher rutting index than the original asphalt. (2) R-F modified WMA had better cracking resistance at a low temperature. The failure energy of the R-F modified WMA was 24.3% higher than the conventional HMA, and the fracture energy of the R-F modified WMA was 7.7% higher than the conventional HMA. (3) The pavement distress prediction results showed the same trend compared with the laboratory testing performance in that the R-F modified WMA helped to improve the IRI, AC cracking, and rutting performance compared with the conventional HMA. In summary, R-F modified WMA can be applied in pavement construction.

Value-Added Use of Waste PET in Rubberized Asphalt Materials for Sustainable Pavement

Waste poly(ethylene terephthalate) (PET) drinking bottles and end-of-life scrap rubber tires are common municipal solid wastes discarded and produced every day, which are usually disposed of in landfills and stockpiles, occupying a great quantity of land and causing serious environmental issues. This study aims to first turn waste PET into two value-added derived additives under the chemical treatment of two amines, namely triethylenetetramine (TETA) and ethanolamine (EA), respectively, and then adopt them in association with crumb rubber (CR) to modify virgin bitumen for preparing various rubberized asphalt mixtures. Subsequently, the high- and low-temperature properties of the rubberized binder modified by PET additives (PET-TETA and PET-EA) were comparatively characterized through dynamic shear rheometer (DSR) and bending beam rheometer (BBR) tests, while the rutting resistance, fatigue resistance, and dynamic modulus of the further fabricated mixtures were evaluated and validated through mixture tests. The results obtained indicate that 2 wt.% PET-TETA and PET-EA contribute to increase the rutting failure temperature of asphalt rubber from 82.2 °C to 85.5 °C and 84.2 °C, respectively, retaining the high grade of PG 82; the low-temperature grade of asphalt rubber slightly decreased from PG-28 to PG-22 as the additive was added; the rut depth slightly changed from 3.10 mm to nearly 3.70 mm; and PET-TETA exhibits the potential to be capable of extending the fatigue life of asphalt rubber in contrast with PET-EA at different stress levels within 450 kPa. Based on the findings of this study, the developed recycling approach is considered to be applicable to not only alleviate the environmental concerns caused by the landfills and stockpiles of those wastes but also make them valuable for building more durable pavement.

Sustainable approach of applying previous treatment of tire wastes as raw material in cement composites: Review

Rubber as an elastomer is difficult to recycle due to the curing process that undergoes in its various applications, highlighting vulcanization. Tires, particularly, represent a significant amount in disposal of rubber, due to the automobile industry growing over the last decades. Several researchers have been studying its use on civil construction, and in concrete. The results obtained in the researches, with scrap tire rubber as received replacing the concrete constituents, indicated significant reductions in the compressive and flexural strengths, as well as in elasticity module. On the other hand, due to the high capacity of rubber to dissipate energy, rubberized concretes may be suitable for architectural application, false facades, stone baking, interior construction, in building as an earthquake shock wave absorber where resistance to impact or explosion is required and as roof top surfaces for insulation and waterproofing. Various studies highlighted the potential of rubberized concrete acting as a cushion due to its high impact resistance. The use of recycled rubber in Portland cement concrete is not technically successful as in asphalts mixtures due to the incompatibility issues caused by chemical composition and stiffness. After observing the drawbacks caused by the addition of rubber, researchers evaluated their causes, and the main reason was the poor adhesion between cement paste and rubber particle, due to the chemical difference in the polarity of the materials, that affects the cement hydration. Meanwhile, some authors are intended to perform some treatments on the rubber material to enhance the interfacial adhesion with cement hydration products and reduce or eliminate the negative effects while keeping the beneficial effects of waste rubber as an aggregate. Despite of a great loss in strength using tire particles as aggregate in concretes, it was accepted in various applications requiring medium to low compressive strength. On the other hand, rubberized concrete strength may be improved by improving the bond properties of rubber aggregates. Some studies highlighted this possibility by pre-treating the rubber.

Analysis of Scrap Tyre Rubber Pad Base Isolated Structure using MATLAB

The structure should be protected from adverse effects of earthquake forces or any seismic vibration. The base isolation technique is used to reduce most of the effects that are caused by these external forces. Isolation is achieved by using installing different types of flexible materials under the structure. Earthquakes cause lots of damage to the health and wealth of an economy. In the current study, a four-story structure with base isolation is analyzed. Scrap Tyre Rubber Pad is used as base isolation material for this study. The structural response is compared with a similar structure having fixed support without isolation. MATLAB software is utilized for determining the values of frequency and mode shapes for a structure. After comparing two structures base isolated structre was found to be more effective to higher frequencies.

Catalyzed pyrolysis of scrap tires rubber

Every day, a huge volume of scrap tires are produced worldwide, and landfill is an ineffective method of disposing of such hazardous waste. Pyrolysis can be used to convert tire rubber into energy, allowing for the management of such waste in the context of a circular economy. The composition and pyrolysis kinetics of granulated (0.6–0.8 mm) scrap tire rubber (TR) were assessed using thermogravimetry (TG). Data on rubber composition revealed that TG is a quick and accurate technique for determining TR composition. The TG tests with catalysts revealed that using alkali (K, Ca, and Mg) carbonates as catalysts improved the thermal degradation rate. The MgCO3 was able to duplicate the rate of TR thermal degradation. Data from a fixed bed pyrolysis reactor revealed oil yields of around 50% in the 673–773 K temperature range. The effect of alkali carbonate catalysts inferred from TG tests was confirmed by catalyzed pyrolysis tests. The calcium and magnesium carbonate catalysts significantly increased the gas product yield, with the CaCO3 catalyst having the greatest drop in oil yield due to likely secondary pyrolysis processes. Because of the low pyrolysis temperature, the acidic catalysts (SiO2, TiO2, Al2O3, and montmorillonite) had almost no effect on the pyrolysis product distribution. For all of the catalysts used, the ATR-FTIR spectra of the produced oils exhibited characteristics similar to those of diesel fuel. Data showed that alkali carbonate catalysts (mainly Mg and Ca), cheap and environmentally benign materials, can be used to tailor the TR pyrolysis products distribution allowing a more profitable process.

Waste-tyre pyrolysis and gasification via the reverse boudouard reaction: derivation of empirical kinetics from TGA data

The pyrolysis of scrap tyre rubber crumbs under nitrogen and treatment with pure carbon dioxide was investigated both isothermally and dynamically up to 1100 °C, at heating rates up to 20 °C min−1. The rubber sample was a mixture of industrially representative tread and sidewall material. Workable, but not definitive, models could be derived from the isothermal analysis: Jander D3 diffusion for the first pyrolysis event under nitrogen up to 550 °C; the Mampel mechanism for high-temperature pyrolysis above 550 °C; and shrinking-particle chemical-reaction control as the rate limiting step for the reverse Boudouard reaction. The isothermally derived pre-exponential factors and activation energies were further refined by non-linear fitting to the dynamic data of all heating rates, and by making both parameters functions of the degree of conversion. In addition, the Sestak-Berggren equation was directly fitted to the full data set, i.e., for all heating rates, also using pre-exponential factors and activation energies that are dependent on degree of conversion. Both the approaches yielded workable engineering kinetics, with the Sestak-Berggren performing worse. With single-value pre-exponential factors and activation energies, the models fitted the data less satisfactorily across the range of heating rates. The required numerical analysis is fully implementable on a commercial spreadsheet.

Parameters of Sand-Tyre Chips Mixture for Hardening Soil Small Constitutive Model

Hardening Soil model with the small strain extension (HSS) is lately one of the most popular constitutive models to describe soil behaviour. It is versatile – includes the phenomena of shear strength, stress history, dilatancy, volumetric and shear hardening, hyperbolic stress-strain relationship in axial compression, stiffness dependency on stress and its degradation with strain, as well as the regain of the high stiffness after sharp loading reversals. Even though the model is advanced and complex, accordingly to its authors, it is relatively easy to calibrate based on results of standard tests and empirical formulas. In this paper an attempt was undertaken to estimate the parameters of untypical anthropogenic soils – mixtures of sand and scrap tyre rubber in order to build a database for future numerical analyses. A literature review was conducted and, eventually, the material parameters were determined based on results of a series of laboratory tests (cyclic and monotonic triaxial with bender elements, direct shear) published by researchers of Wollongong University of Australia.

Hybrid double skin FRP – Steel column with rubberised concrete infill under axial loading

The use of scrap tyre rubber in concrete is an effective sustainable solution that lessens the accumulation of tyres in the landfill and related environmental hazards. Extensive research on the behaviour of rubberised concrete over the past few years has outlined some excellent mechanical properties of this material such as enhanced ductility, energy dissipation, and impact resistance but also an associated weakness of having reduced strength. In this paper, a hybrid double-skin tubular column with rubberised concrete infill is proposed to provide effective lateral confinement and longitudinal reinforcement to minimize the reduced strength of rubberised concrete. This double-skin tubular column called “hybrid RuDSTC” comprises an outer filament wound CFRP or GFRP tube, inner steel tube with rubberised concrete infill. An experimental investigation on the behaviour of the proposed column under axial compressive loading is carried out. The parameters of the investigation are the type and thickness of the FRP tube and the percentage of rubber aggregates such as 0%, 15%, and 30% by weight. Axial stress, axial strain, lateral strain, and failure shapes of the columns are determined and discussed. Results show that both the filament wound CFRP or GFRP tube and steel provide effective confinement to increase the compressive strength and the peak and ultimate strain capacities of the hybrid RuDSTC columns. An increase in the amount of rubber aggregates results in lower values of brittleness index which indicates better ductility of the columns. Performance of CFRP and GFRP enclosed columns based on their diameter to thickness ratio and the steel confined double-skin tubular columns are compared. The proposed novel hybrid column provides a sustainable solution with applications in seismic-prone regions and mining infrastructure.

Numerical and experimental analyses for rubber-sand particle mixtures applied in high-filled cut-and-cover tunnels

With the rapid development of the automobile industry and transportation, the disposal of scrap tires has become an internationally recognized economic and environmental problem. Fortunately, high-filled cut-and-cover tunnels (first construction and then layered backfill) provide ideal solutions for waste treatment and resource reuse as mixtures of scrap tire rubber particles and sand are used as lightweight fill material (LFM) in high-fill cut-and-cover tunnels (HFCCT). Because the backfill above the cut-and-cover tunnel (CCT) requires a large quantity of material, an appropriate ratio of scrap tire rubber particles and sand should be selected as the LFM mixture. If LFM of different thicknesses is buried above the CCT, it will inevitably bring varying degrees of influence on the earth pressure around the CCT, leading to structural deformation and soil settlement above the CCT. In this paper, a method of combining numerical simulation and model test is presented to help analyze the macroscopic and micromechanical properties of LFM through the stress–strain change and the contact force chain distribution. In the model test, certain factors influencing the earth pressure, the structural deformation, and the soil settlement mentioned above are considered, including the fill height and the embedding depth of the LFM. The results show that when the rubber fraction by volume (RF) is between 30% and 45%, the deformation and load-bearing capacity of the LFM are the most stable. Moreover, a suitable rubber fraction by volume (RF = 40%) and backfill height (between 0.63 ∼ 0.83 times the height of the CCT) can eliminate the stress concentration at the top center of the CCT.

Catalytic potential of low-cost natural zeolite and influence of various pretreatments of biomass on pyro-oil up-gradation during co-pyrolysis with scrap rubber tires

This study investigates the influence of low-cost natural zeolite (NZ) catalyst, metallic content and various pretreatments of rice straw (RS) on quality and quantity of oil derived from co-pyrolysis and catalytic co-pyrolysis of RS and scrap rubber tire (SRT). Oil obtained from co-pyrolysis of combined acid-washed and torrefied RS (WT-RS) and SRT (WT-RS/SRT) had 41% less oxygenates, 17% more hydrocarbons (HCs) and a significant amount of levoglucosan compared to the combination of raw RS and SRT (R-RS/SRT). Besides, char from WT-RS/SRT combination had more HHV (30.15 MJ/kg) than that of R-RS/SRT combination (26.85 MJ/kg). NZ incorporation into co-pyrolysis enhanced deoxygenation by 34% for catalytic combination of R-RS/SRT/NZ than non-catalytic co-pyrolysis of R-RS/SRT combination whilst the combination of WT-RS/SRT/NZ encountered 77.27%, 61.53% and 65.51% more deoxygenation than R-RS/SRT, WT-RS/SRT and R-RS/SRT/NZ combinations, respectively. An increase in HCs was found to be 40% and 31.25% for WT-RS/SRT/NZ contrary to WT-RS/SRT and R-RS/SRT/NZ, respectively. Additionally, 69.23% more mono aromatics along with more valuable gaseous composition were obtained in WT-RS/SRT/NZ than R-RS/SRT/NZ. HHV and physical characteristics of oil were superior for WT-RS/SRT/NZ. Results showed co-pyrolysis of pretreated RS-SRT as an effective route to improve product quality, which was further improved by the catalyst incorporation.