Rubber Ash Research Articles

Effect of Water-Cement Ratio on Mechanical Properties of Rubberized Fly Ash Concrete

One of the efforts to reduce the dependency of concrete production on natural resources along with carbon reduction is by utilizing recoverable materials as concrete constituents such as crumb rubber from scrap tires and fly ash from industrial waste. This study aims to investigate the mechanical properties of rubberized fly ash concrete which utilized crumb rubber and fly ash as a replacement for a proportion of fine aggregate and cement, respectively. Crumb rubber was used to replace 5 and 10% fine aggregate while fly ash was used to replace 10% OPC by weight. Three different water-binder (w/b) ratio, 0.55, 0.50 and 0.45, were used. The concrete specimens were prepared and tested for their density, compressive strength, splitting tensile strength, and flexural strength. Result gathered from the experimental works show a reduction in properties of rubberized concrete when compared to conventional concrete. By using a lower w/b ratio, the reduction tends to decrease and rubberized concrete with 0.45 w/b ratio recorded comparable density and strength to that normal concrete. The use of a lower water-binder ratio in concrete mix improved the strength of rubberized fly ash concrete equivalent to the normal concrete, allowing for usage of green materials in real building construction.

Investigating mechanical properties and durability of concrete containing recycled rubber ash and fibers

This article investigates the suitability of utilizing end of life rubber tyre particles in concrete as fine aggregate. Rubber ash and rubber fibers were used to develop two series of rubber ash concrete (series I) and hybrid concrete (series II) mixes. The natural fine aggregate was replaced by rubber ash (by volume of 5%, 10%, 15% and 20%) in series I; whereas in series II, the amount of rubber ash was kept constant at 10% and rubber fiber was introduced as replacement of fine aggregate (by volume of 5%, 10%, 15%, 20% and 25%). The concrete mixes were evaluated for compressive strength, flexural strength, resistance to impact loading, fatigue loading, water penetration and shrinkage strain was evaluated. It was observed that inclusion of rubber ash resulted in the improvement of impact resistance of concrete. The results also show that up to 10% rubber ash and rubber fibers can be utilized as fine aggregate to develop feasible and durable rubberized concrete pavements, crash barriers and paver blocks.

Incorporation of rubber ash as a partial substitute of fine aggregates in concrete

The construction industry is responsible for a high consumption of natural resources, demanding high quantities of aggregate materials for use in construction. In addition, large quantities of rubber waste generated worldwide have emphasized the need to find practical reuse applications. The present study partially replaces fine aggregates by ash from a co-processing of milled and burned conveyor belt rubber waste. Test specimens with ash concentrations of 0%, 5%, 10%, 15% and 20%, were made comparing its workability, mechanical axial resistance and absorption of water by capillarity. It was concluded that the partial replacement of sand by 5% of rubber ash has improved the traditional concrete mixture, with better workability, less amount of water, leading to a greater resistance to axial compressive and acceptable absorption of water. Thus, the results confirm that the concrete with incorporation of rubber ash is a potential alternative technology to achieve sustainable development in the construction industry.

Effect of Admixtures on Mechanical Properties of Cementitious Mortar

In the current study, the primary focus is to investigate the effect of Styrene Butadiene Rubber (SBR), silica fume and fly ash on compressive and flexure strengths of cementitious mortar. Three types of specimens are prepared; the first series comprises of control specimen; the second one consists of the mortar’s specimen modified with SBR and the third one consists of the mortar’s specimen modified with SBR in a combination of fly ash and silica fumes. Mortar samples are cast in the weight ratio of 1:2.75 (cement: sand). The SBR is added at a rate of 20% of the mass of cement. The water to cement ratio (W/C) is kept at 0.5 for control specimens and the quantity of mixing water in SBR-containing samples is reduced by the same amount as the SBR is added: The adjustment is meant to obtain same consistency for all the specimens. 20% fly ash and 2.5% silica fume are added to the mortar as replacement of cement. Compressive and flexure tests are carried out according to ASTM standards. Moreover, SEM is also performed on samples at the age of 28 days. Studies reveal that SBR and SCMs reduce the mechanical strength of the mortars. SEM and EDS studies show that SBR hinders the formation of albite, whereas silica content from silica fumes and fly ash converts CaCO3 to Wollastonite (a white loose powder), which is responsible for the reduction of mechanical strength. The study also confirms that the addition of SBR in place of water hinders the formation of primary and secondary hydration products. Doi: 10.28991/cej-2020-03091610 Full Text: PDF

Flexural behavior of rubberized concrete interlocking masonry walls under out-of-plane load

Waste and industrial by-products, such as crumb rubber and fly ash, are being utilized as raw materials for making various masonry products. Rubberized concrete interlocking brick (RIB) is a newly developed product incorporated 10% crumb rubber, as a partial replacement for sand, and 56% fly ash, as a partial replacement for cement. The study experimentally emphasized understanding the behavior of masonry walls made of the developed rubberized interlocking bricks under out-of-plane load, with and without precompression load. The compressive strength of the developed loadbearing RIB was 18.4 MPa. The results of flexural strength, moment–curvature relationship, displacement responses, joint opening, and failure modes for masonry walls made of the developed RIB under lateral load parallel to the dry bed joints are discussed. An analytical analysis to predict the cracking flexural load is presented and compared with the experimental results. The results show that by increasing the pre-compression load, flexural strength, and moment capacity of the rubberized interlocking masonry walls increased linearly. The lateral displacement was 10.82, 24.99, and 29.69 mm for masonry walls subjected to a 0, 56, and 112 kN pre-compression loads, respectively. Flexural failure along the width of masonry walls with a course opening at mid-height was the dominant failure mode. It can also be concluded that the theoretical cracking flexural load closely matches the laboratory load.

Effect of rubber ash on mechanical properties of Al6061 based hybrid FGMMC

The usage of rubber ash as a reinforcement material for aluminium composite has never been used, this work pertains to one such experimentation. In this work rubber ash and boron carbide in varying proportions to reinforce Aluminium based Hybrid functional grade metal matrix composite (FGMMC). The fabrication is done using the centrifugal casting method. The rubbish ash and B4C content are varied and the samples are tested to get the ratio with the optimal mechanical properties. The tensile strength of the Aluminium based Matrix Composites (AMC) seems to increase with an increase in % weight of rubber ash. Further analysis of the composite reveals that the B4C and rubber ash particles were evenly distributed in the AMC. This can be confirmed using SEM imaging. This work studies the usage of boron Carbide and rubber ash to reinforce the FGMMC by comparing its properties to conventional AMC’s. The mechanical properties along with the cost factor are weighed to arrive at a convincing solution.

Hardened properties of concrete with different proportion of crumb rubber and fly ash

The utilisation of waste materials in concrete is one of the sustainable construction approaches introduced in the industry that can indirectly reduce the environmental issues arisen from the disposal problem of the wastes. The aim of this study is to investigate the hardened properties of rubberised pozzolanic concrete (RuPC) with different proportion of crumb rubber and fly ash as partial fine aggregate and ordinary Portland cement (OPC) replacement, respectively. The crumb rubber content replacing fine aggregate is in the range of 0% to 20% while fly ash replacing cement ranges from 0% to 30%. Testing of RuPC with different percentage of crumb rubber and fly ash were performed at the age of 28 days for density, compressive, splitting tensile and flexural strength, and were compared with properties of control specimens. Results showed that the density of RuPC decrease with increase in crumb rubber and fly ash content. The overall strength of RuPC decrease as crumb rubber content increase in which 5% crumb rubber show the least reduction in strength. Replacing 10% cement with fly ash shows improvement in the strength of RuPC when compared to specimens without fly ash, however still lower than strength of control specimen. The optimum crumb rubber replacement is 5% while fly ash is 10% to avoid significant reduction in strength.

Performance of Crumb Rubber and Nano Fly Ash Based Ferro-Geopolymer Panels under Impact Load

This paper presents an experimental investigation into the impact performance of Ferro-cement panels incorporating a significant proportion of geopolymer mortar. This panel could be an effective replacement for prefabricated roof and floor deck construction elements. In this study, the geopolymer mortar includes wastes disposed from industries like ground granulated blast furnace slag (GGBFS) and flyash as their base material which contributes to reduced CO2 emission. The pore filling and element densifying mechanism is enhanced by the addition of Nano flyash. The fine aggregate is replaced up to 5% with treated tyre crumb rubber which can be utilized as a sustainable construction material. The cast panel was cured at 80oC for 48 hours in the oven. The incorporation of Expanded Metal Mesh into geopolymer mortar results in higher impact load absorption capacity rather than other kind of reinforcing meshes. The GGBFS based Geopolymer results in 17% higher compressive strength than fly ash based geopolymer because of its good bonding nature. The Nano fly ash based geopolymer gives 35 MPa in compressive strength and 902.52 joules in impact energy absorption which is greatest among all panels because of its densifying effect of mortar.

Characteristic compressive strength correlation of rubberized concrete interlocking masonry wall

The rapid growth in the construction industry has dictated the utilisation of the eco-friendly materials and recycling of wastes to produce sustainable products. In this study, rubberized concrete interlocking bricks have been developed by utilising crumb rubber (10%) and fly ash (56%) as partial replacements of sand and OPC, respectively. It is aimed to develop mean and characteristic compressive strength correlations of rubberized concrete interlocking hollow and grouted wall systems, corresponding to rubberized concrete interlocking brick and prism strengths. A systematic investigation of 20 rubberized concrete interlocking brick units, 10 hollow and grouted rubberized concrete interlocking prisms and 10 identical hollow and grouted rubberized concrete interlocking wall panels were cast, constructed and tested under compressive load. Results were statistically analysed and the design-charts for the mean and characteristic compressive strength of masonry were used. The results obtained for the strength of rubberized concrete interlocking brick, prism and wall revealed a normal distribution with 5% significant interval. Four types of regression models were proposed for statistical analysis and the best fit model was identified based on r2 (correlation coefficient). The power model for the mean and characteristic strength curves presented the best fit to the sorted data. The cracking pattern and modes of failure of the tested specimens were discussed. The relationships for characteristic strengths of rubberized concrete interlocking masonry hollow and grouted wall were derived in terms of rubberized concrete interlocking unit and prism strength and found to be fkw = 1.533fb0.290, fkw = 2.178fb0.337 and fkw = 1.119fp0.659, fkw = 1.023fp0.731, respectively.

Additive Effect of Piriformospora Indica Fungus and Rhodococcus Erythropolis Bacteria on Bio-Remediation of Pyrene in a Pb-Polluted Soil Treated With Tire Rubber Ash

Background and Purpose: This research was conducted to evaluate the effect of Piriformospora indica fungus (P. indica) and Rhodococcus erythropolis (R. erythropolis) bacteria on bio-remediation of pyrene in a Pb-polluted soil that was treated with tire rubber ash.
 Materials and Methods: Treatment consisted of applying tire rubber ash at the rates of 0 and 300 mg/kg soil, soil polluted with pyrene at the amount of 0 and 100 mg/kg soil, soil pollution with Pb (0, 400 and 800 mg/kg soil), and finally plant inoculated with P. indica fungus and R. erythropolis bacteria, and the plant used in this experiment was canola. After 60 days, plants were harvested and plant Pb and Zn concentration was measured using atomic absorption spectroscopy (AAS). The pyrene concentration in the soil samples were extracted by soxhlet using n-hexane and a 1:1 (v/v) dichloromethane during 24 h and measured according to the Besalatpour et al. (2011). The basal soil microbial respiration was measured as evolved CO2.
 Results: A significant increase (P=0.05) by 15.1% was observed in pyrene degradation in soil when plant inoculated with P. indica and R. erythropolis. However, soil pollution with Pb significantly decreased the pyrene degradation in the soil. At the same time, adding tire rubber ash to the soil significantly increased the plant biomass and pyrene degradation.
 Conclusion: Plant inoculation with P. indica and R. erythropolis had an additive effect on pyrene degrading (bio-remediation) in soil that is an important factor in environmental studies. However, soil pollution with heavy metals showed an adverse effect on it.

Performance of Crumb Rubber Incorporated Ferro Geopolymer Panels under Flexure

This research work presents the overview of geopolymer mortar application into the ferro cement panel with the incorporation of crumb rubber and Nano fly ash. The geopolymer mortar is prepared by using industrial wastes as a base material such as fly ash and ground granulated blast furnace slag (GGBFS) which generally helps to reduce the level of CO2 emission. Also, the recycled tyre crumb rubber is utilized as a sustainable innovative construction material which is used a partial substitution for sand upto 5% for enhancing the ductility without any strength degradation. These reduces land fill problems and ground water quality degradation problems. Crumb rubber has the ideal capacity to absorb energy from static and other kind of loads. The geopolymer binder preparation is done by utilizing material such as fly ash, GGBFS, alkaline liquid made of NaOH and Na2SiO3 , Nano fly ash. The Nano fly ash is used as an additive which helps in increasing the strength and durability of the element by its pore filling capability. This project aims to enhance the strength of fly ash based geopolymer mortar with the help of GGBFS incorporation. The molarity of alkaline activator, solution to binder ratio and silicate to hydroxide ratio is fixed as 12, 0.4 and 1.5 throughout the process. The mortar cubes and panels were heat cured under hot air oven at 80ᵒ C for 48 hours. The mechanical behavior of geopolymer mortar is assessed by compressive strength test water absorption test. The panel is made of high strength geopolymer mortar and expanded metal mesh with chicken mesh for obtaining higher energy absorption capacity with good deforming ability and less crack pronouncement. The investigation involves finding the initial crack load, ultimate failure load and residual flexural strength ratio. The results show that the tyre inclusion enhances the flexural strength of the ferro geopolymer panel by means of its ductile enhancing capacity

Effect of Crumb Rubber, Epolene (EE-2), and Date Palm Ash as Modifiers on the Performance of Binders and Mixtures: A Sustainable Approach

The only type of conventional bitumen (PG 64-10) available in the Kingdom of Saudi Arabia (KSA) does not meet the temperature requirements of most of the kingdom’s regions. Hence, the binder needs to be modified to improve the performance of flexible pavements at high temperature and heavy traffic loading. In order to meet the requirements of the Superpave Performance Grade (PG), crumb rubber (CR), epolene (EE-2), and date palm ash (DPA) were used as asphalt additives in different percentages (4%, 8%, 12%, and 16% by weight of bitumen). Viscosity and rheological tests as well as stability and indirect tensile tests were performed on binders and asphalt mixtures. The binders modified with CR, EE-2, and DPA showed improved rheological and performance properties as compared to conventional binder. Similarly, the PG of conventional asphalt was upgraded with the addition of different percentages of the modifiers. Furthermore, this study also aimed to help the environment by minimizing and recycling wastes in road construction processes to achieve sustainability.

Waste rubber ash modified by silane coupling agent as reinforced filler in acrylonitrile butadiene rubber cured by ionising radiation

ABSTRACT Composites of acrylonitrile butadiene rubber loaded by different concentration (0–40 parts by weight per hundred parts of rubber (phr)) of waste rubber ash (WRA) that treated by Vinyltriethoxysilane (VTES) have been prepared, and then the composites subjected to gamma radiation at different doses ranged (0 up to 150 kGy) to desire curing. The WRA powder that treated by VTES silane (WRA-Sn) was characterised by different tools like Fourier transforms infrared spectroscopy and X-ray diffraction. Mechanical properties of composites tensile, elongation and modulus were shown enhancement by increasing the treatment of waste rubber and also by increasing irradiation dose. The crosslink density of composites increases by increasing WRA-Sn content and irradiation dose. The thermal stability of a variety of composites was done using thermogravimetric analysis. The results show that the WRA-Sn improves its thermal stability of composites.

Influence of Tropical Environment on Electrical Properties of Electrical Insulation Materials

The development of optimal electrical insulation materials in the tropics continues. One of the development models is to look for fillers that allow it to be mixed with insulating materials (polymers, ceramics, and glass). This study aims to obtain the properties of electrical insulation materials in the form of polymeric materials (silicon rubber) which are filled with fly ash (coal-fired power plant waste) so that it can be used as a high-voltage electrical insulator. The activity that has been carried out was testing the performance of electrical insulating materials filled with fly ash under conditions under high electric fields and tropical environments. The research was conducted at the Electrical Engineering Building, Hasanuddin University, Makassar City, Indonesia. The performance evaluation of electrical insulation materials (silicon rubber plus fly ash) refers to the results of measurements of water diffusion characteristics and relative permittivity characteristics. The results of the study were in the form of information about the feasibility of coal-fired power plants to be used as fillers for electrical insulators in tropical environments. The results of this study are Fly ash added to silicone rubber to improve the electrical properties of the insulating material.

Experimental Investigation on Concrete with Tire Rubber and Fly Ash

Experimental Investigation on Concrete with Tire Rubber and Fly Ash

Mechanical properties of crumb rubber-rice husk ash concrete as a rigid pavement material

Waste tyres accumulate very quickly in a landfill as a result of the fast development of the transport industry, and mainly automobiles. The polymeric waste has limited usage and is rarely employed in a highly economic and viable product. A rigid pavement material needs to have high mechanical properties and durability when exposed to aggressive environments. In this research, a combination of waste tyre with rice husk ash and Portland Cement Composite (PCC) as a primary binder was designed to produce concrete that meets the requirements of flexural strength value of the rigid pavement based on the Indonesian Standard from Bina Marga 2018. Eight mixes with a variety of water/cement ratio (0.30-0.40), crumb rubber (2.5-7.5%), and rice husk ash (7.5-10%) were designed in this research. The control mix was PCC concrete. The crumb rubber substituted the fine aggregate content, while the rice husk ash replaced the cement content in concrete. The specimens were cast and subsequently cured in water pond up to 28 days. The mechanical properties of concrete, namely compressive strength and flexural strength were determined for all variations. Based on the results, Mix 1 with w/c ratio of 0.30, crumb rubber of 5%, and rice husk ash of 10%, performed both the highest compressive strength and flexural strength values of 36.38 MPa and 4.53 MPa, respectively, after 28 days. Both values fulfilled the requirements of the Indonesian Standard Bina Marga 2018. It can be concluded that an appropriate combination of crumb rubber and rice husk ash improves the mechanical properties of the concrete and has potential as a rigid pavement material.

Statistical analysis of mechanical properties of mortars with fly ash and waste tire rubber

Abstract This article aims to perform statistical analysis on the inclusion effects of waste tire rubber and fly ash from thermoelectric plants as mortar components for coating buildings. Reference mortars and mortars containing 5% and 10% rubber with a maximum grain size of 0.71 mm and mortars containing fly ash particles with a diameter of 45 μm were produced. Mortars containing rubber replaced 5% and 10% of the fine aggregate mass by this material and fly ash was added in 10% and 20% proportions compared to the cement volume. A 3² factorial experiment was performed on the mechanical properties of the compressive strength of mortars, applying analysis of variance (ANOVA) and surface response. The rubber waste material contributed to the decrease in compressive strength of the mortar and that factor displayed the highest significance in the response variable.

Natural rubber composites for solid tyre used for forklift tensile properties and morphological characteristics

The engineering of natural rubber and synthetic rubber into vulcanized solid tyres for forklifts has been carried out to obtain the optimum ratio of formula and process temperature according to the standards of solid tyre commercial forklifts. Composite formulated materials consist of natural rubber, synthetic rubber, carbon black, silica, calcium carbonate, and coal fly ash, while the temperature, time, and other process materials are fixed variables. The results of testing the mechanical properties of forklift solid tyres for formula C are as follows: specific gravity1.195 g/cm3 hardness78 Shore A, tensile strength 17.3 Mpa, tear strength 55.2 kN/m, abrasion resistance 160.8 mm3 modulus 300% is 6.6%, and ozone resistance at 50 pphm, 20% strain, 24 h, 40 °C is no cracks.

Waste ashes as catalysts for the pyrolysis\u2013catalytic steam reforming of biomass for hydrogen-rich gas production

Combustion ashes from coal, refuse-derived fuel (RDF) and waste tyres have been investigated as potential catalysts for the production of a hydrogen-rich gas from waste biomass. The process used a two-stage reactor involving pyrolysis of the biomass followed by catalytic steam reforming of the evolved pyrolysis gases using the ash catalysts. The ashes were also impregnated with 10 wt% nickel to determine the influence on hydrogen production. In the presence of the ash samples, the total gas yield and hydrogen yield significantly increased, particularly for the refuse-derived ash. The ash samples contained a high metal content, including Al, Ca, Mg, Cu and Fe, K, Na and Zn. All such metals have been reported to act as catalysts for hydrogen production. In the absence of catalyst, the total gas yield from the biomass was 39.9 wt% which increased to 52.7 wt% with the tyre rubber ash, to 50.3 wt% with coal ash and 59.5 wt% with RDF ash. The highest hydrogen yield of 7.90 mmol g−1biomass was produced in the presence of the RDF-derived ash, representing 29.73 vol% H2. Addition of nickel to the combustion ash samples showed a further significant increase of ~ 20% in the yield of hydrogen.

Investigation of the Mechanical Properties of Engineered Cementitious Composites with Low Fiber Content and with Crumb Rubber and High Fly Ash Content

Engineered cementitious composites (ECCs) are a type of micromechanically-designed cementitious composite reinforced with a moderate volume fraction of short fiber, typically 2% by volume. ECCs form steady-state multiple cracking that considerably improves the tensile strength and ductility of traditional concrete. In this study, the properties of matrix and the interface of ECCs were tailored through the use of crumb rubber, different types of sand, and different replacement levels of cement with fly ash. The study examined the effect of sand replacement with crumb rubber (20% by volume), two types of river sands (coarse and fine), increasing the content of class F fly ash (up to 75% cement replacement), and low fiber content (1.75%) on the mechanical properties of ECCs. Compressive strength, uniaxial tensile, and third-point bending tests were performed to characterize the properties of ECC mixes. Experimental results demonstrated that increasing fly ash content and using crumb rubber favored ductility of the composites. However, higher fly ash contents and a low water-to-binder (W/B) ratio produced lower strengths as these limited the pozzolanic reaction of fly ash making it act partially as a filler. While incorporation of crumb rubber showed adverse effects on the tensile strength of ECC materials (up to 26% decrease), the tensile ductility of ECC materials improved significantly (up to 434% improvement). Moreover, the implementation of different types of sand produced minor effects on the mechanical properties of ECCs. Overall, a tradeoff between the strength and ductility of the composites was detected, which highlights the implications of matrix/interface tailoring in the overall performance of ECC.