Coarse Aggregate Replacement Research Articles

Glass Fiber for Improved Behavior of Light Expanded Clay Aggregate Concrete Beams: An Experimental Study

Concrete developed from light expanded clay aggregate (LECA) and glass fiber has good performance, durability, and sustainability. Towards this, the experimental investigation was designed to study cubes, cylinders, and simply supported beams. Four mixtures had LECA volume of 0%, 75%, 85%, and 95% as coarse aggregate replacement and glass fiber content volume of 2% (N, L75, L85, and L95), and the other two mixtures had 75% LECA and glass fiber content of 1% and 1.5% (L75-F1 and L75-F1.5). Results compared to normal concrete showed the weight reduction of samples while adding more glass fiber caused slump reduction in contrast to LECA. Increasing glass fiber volume in the mixture had a negative influence on tensile strength while causing compressive strength enhancement. Moment resistance and energy absorption capacity of L85 were enhanced by 7.5% and 10.3%, respectively. For L75-F1 specimens, the beam stiffness and ductility were enhanced by 14.8% and 14.3%, respectively.

Material properties of ITRAC and cyclic behavior of double steel plate composite shear wall filled with ITRAC

An innovative iron tailing and recycled aggregate concrete (ITRAC)-filled double steel plate composite shear wall (ITRAC-CSW) was proposed to promote the application of the fabricated composite structures and the green build materials. Firstly, the mix proportion of ITRAC was studied through the test of six groups of ITRAC samples by changing the recycled coarse aggregate (RCA) replacement ratio and water-binder ratio. Favorable mechanical properties and the corresponding mix proportion was obtained. The elastic modulus calculation and the constitutive model of the ITRAC were obtained based on the test results. Subsequently, three full-scale ITRAC-CSW specimens were fabricated using ITRAC with the 100% RCA replacement ratio and tested under the cyclic lateral load and constant axial load. The failure mode and deformation mechanism of the specimens were analyzed through experimental phenomena. The seismic performance of the specimen was explored by comparing the load–displacement curves, stiffness degradation, and energy dissipation capacity. The analysis revealed that the ITRAC-CSW exhibits good bearing capacity, stiffness, and energy dissipation capacity which can be used in practical project.

Atili Seed Shell as Partial Replacement of coarse Aggregate in No-fines Concrete

Atili Seed Shell as Partial Replacement of coarse Aggregate in No-fines Concrete

Use of crushed bricks and recycled concrete as replacement for fine and coarse aggregates for sustainable concrete production

The growing concern over the significant ecological changes requires sustainable developments in all fields. Concrete production is one of the largest consumers of natural resources as it consumes a huge volume of natural fine and coarse aggregates, which constitute 70% - 80% of the concrete volume. It is evident that such large amount of concrete production in the growing construction industry puts significant impact on the use of natural resources and the environment. Hence, investigating the use of recycled materials to replace the finite natural resources became evident and is the focus of researchers. In this research, the use of waste crushed bricks (CB), and crushed recycled concrete (CRC) as a partial replacement of fine and coarse aggregates in concrete was studied. The replacement ratios of 10%, 50%, and 100% by weight of either fine or coarse aggregates were used. Eight concrete mixes with 168 specimens were tested for compressive, splitting tensile as well as, flexural strength. All tests were carried out at ages of 7, 28 and 56 days. The results indicated that there is a feasibility of using bricks and concrete wastes in concrete mix as a partial replacement of course and fine aggregates. It is deduced that a 50% replacement ratio of coarse aggregate with crushed concrete resulted in a 30%, 25%, and 23% increase in compressive, tensile, and flexural strengths, respectively. While 50% replacement ratio of fine aggregate with crushed bricks resulted in a 23%, 28%, and 19% increase in compressive, tensile, and flexural strengths, respectively. The most effective mix was at 50% replacement ratio of coarse aggregate with crushed concrete in combination with 50% replacement ratio of fine aggregate with crushed bricks. The results of this mix showed 32%, 28%, 26% increase in compressive, tensile, and flexural strengths, respectively.

Light Emitting Concrete by Replacing the Coarse Aggregate with Industrial Glass Waste (100%,70%,50% Replacement)

The project involves the development of light-emitting concrete by replacing coarse aggregate with leftover shards of industrial glass, which act as the new type of innovation on this field. The discarded glass will be reused in this project, which will contribute to the development of transparent concrete. This is characterized by its ability to transmit light. This material can be used for various applications and is expected to give a new image to concrete. This type of concrete is commonly used in smart construction projects. It can be used to create a sense of the structure's stress and improve the appearance of the building.

Effects of Environmental Waste Plastic Bottle Cover (EWPBC) on Physical and Mechanical Properties of Concrete

The rapid industrialization and urbanization in many countries of the world is leading to great infrastructural development which in turns result to problems like shortage of construction materials and increased productivity of wastes – which has caused environmental issues due to inadequate recycling and disposal facilities. Construction industry is in need of materials which can increase the strength of concrete structures with low cost and less environmental impact. This research is aimed at addressing such issues by investigating the effect of environmental waste plastic bottle cover (EWPBC) on the physical and mechanical properties of concrete. EWPBC samples was collected within the environs and used at different percentage (0%, 12.5%, 25%, 50% and 100%) replacement for coarse aggregate. Physical properties of the materials were investigated and found to be in accordance with relevant specifications. Mechanical properties such as compressive strength and flexural strength tests were also carried out in line with relavant codes of practice. The compressive strenght increases with days of curring and at 12.5% EWPBC, the strength is 4.7% higher than the conventional concrete. The flexural stress is also higher than that of the conventional beam sample at 12.5% EWPBC. The flexural strain is 0.00248-0.0036 and within the specified acceptable limit (0.002-0.0035) for concrete with grade less than or equal to C50/C60. This shows a promising properties at 12.5% EWPBC replacement and also a reduction in cost. It was concluded that EWPBC can be used as substitute for aggregates and also a means of reducing environmental wastes and cost of disposal of such waste.

Influence of elevated temperature on compressive strength of LD slag aggregate concrete

PurposeThis study aims to investigate the compressive strength of concretes incorporating Linz-Donawitz slag (LD slag) as partial replacement for natural fine and coarse aggregates and compare them with traditional concrete.Design/methodology/approachThe natural fine and coarse aggregates were replaced by weight simultaneously up to 100% with LD slag aggregates at an incremental increase of 20%. Concrete of grades M20, M25, M30, M35 and M40 were cast, cured and tested with standard cube specimens to study the density and compressive strength of reference and LD slag aggregate concretes (LDSACs). The concrete specimens were exposed to elevated temperatures, i.e. 100 to 900 °C at an equal interval of 100 °C and tested to study the variation in density and residual compressive strength.FindingsThe results from the experiments reveal that the LDSAC yields a higher density than that of the reference concrete and also undergo less density variation when exposed to elevated temperatures. In addition, the residual compressive strength of LDSAC specimens was significantly higher than that of the reference concrete.Research limitations/implicationsLD slag is believed to be stronger and more durable than locally available limestone aggregates or blast furnace slag. Moreover, it is necessary to study its strength and other properties to determine whether it can be successfully used as an aggregate in concrete universally.Practical implicationsUse of LD slag as aggregates in concrete will convert LD slag into a value added product and as an alternative to the existing natural aggregates which will help in maintaining ecological balance and save valuable lands.Social implicationsThe economically weaker section of the society may now use LDSAC as waste utilization will bring down the overall cost and hence it will benefit people on large scale.Originality/valueUse of LD slag as aggregate in concrete can help find an alternative to the existing natural aggregates which will save the ecosystem and at the same time help in reducing the industrial waste on a large scale.

Influence of micro basalt and recycled macro polypropylene hybrid fibre on physical and mechanical properties of recycled aggregate concrete

With the increasing need to promote “circular-economy” based design in the construction industry, this study developed a new hybrid fibre-reinforced recycled aggregate concrete (FRRAC) with recycled macro polypropylene fibre (PF) and micro basalt fibre (BF). A ternary binder system has been adopted using supplementary cementious materials (SCMs), which are ground granulated blast furnace slag (GGBFS) and silica fume (SF) to reduce the cement content in the proposed composites with recycled coarse aggregate (RCA) replacement ratio at 50% and 100%. The fibre dosage amounts adopted in this study were 4, 6 and 8 kg/m3 for PF, and 4 and 6 kg/m3 for BF in the proposed hybrid combinations. The laboratory tests were undertaken to investigate and quantify the physical and mechanical properties, supported by scanning electron microscopic (SEM) and energy dispersive x-ray (EDX) studies at the microstructure level. The results indicated that the mechanical properties of recycled aggregate concrete (RAC) can be improved by adopting the proposed hybrid fibre combinations concerning strength and ductility. Increasing RCA % replacement led to a reduction in the quasi-static mechanical properties. The proposed hybrid fibre addition into RAC could achieve up to an improvement of 17.5% and 23% for split tensile and flexural strength, respectively. Based on overall performance, a hybrid fibre combination of 6 kg/m3 PF and 6 kg/m3 BF is recommended for adoption in RAC, aimed towards structural applications.

Experimental investigation and SVR model to predict the mechanical properties of RAC by enhancing the characteristic of RCA using surface treatment method along with modified mixing approach

The present study aims to make the concrete prepared with recycled concrete aggregate (RCA) more sustainable by evaluating workability and mechanical strength, i.e., compressive, flexural, and splitting tensile strength of recycled aggregate concrete (RAC). In the present study, RCA is used as a replacement for natural coarse aggregate, and replacement is done by 20%, 40%, 60%, 80%, and 100%. In the context of making RAC more sustainable, a modified two-stage mixing approach (M-TSMA(sp-ggbs)) is adopted. In this mixing approach, cement is replaced by 10% of silica powder and ground granulated blast slag (GGBS) and mixed with water to prepare a slurry, in which RCA is added in the pre-mixing stage. It is observed that the mechanical properties of concrete are slightly improved. Further, to improve RCA characteristics, RCA treatment is done using two surface treatment solutions, HCl and Na2SiO3; (a) RCA is soaked in three different molarities, i.e., 0.5 M, 1 M, and 1.5 M of HCl solution, for 1 and 7 days, and (b) RCA is soaked in 15%, 30%, and 45% concentrations of Na2SiO3 solution for 1 and 7 days. The RCA showing the best characteristics regarding water absorption, impact, and crushing value is considered for preparing the concrete mix. Now, the treated RCA is used to prepare sustainable RAC in conjunction with M-TSMA(sp-ggbs). The experimental results show that the workability of all concrete mixes is within the desired range. Moreover, the mechanical properties are significantly improved by considering RCA treated with 45% concentrations of Na2SiO3 soaked for 7 days at a 60% replacement level along with M-TSMA(sp-ggbs). Further, this article used support vector machine regression (SVR) to predict the compressive, flexural, and splitting tensile strength based on the experimental values and the input variables. The SVR model predicted the compressive, flexural, and splitting tensile strength with 97%, 95%, and 88% accuracy.

Performance of recycled Bakelite plastic waste as eco-friendly aggregate in the concrete beams

The use of plastic waste as a partial or complete replacement for coarse aggregate in concrete mixtures has been studied in recent years. However, the quality and quantity of coarse plastic waste particles have been a challenge. This study aims to investigate the mechanical performance of concrete with Bakelite plastic waste as a partial replacement for coarse aggregate. Six different concrete mixtures with various Bakelite dosages, ranging from 0 % to 10 %, were tested. The results indicate that the addition of Bakelite plastic alters the behaviour of the concrete and reduces compressive and flexural strengths at lower dosages. The inclusion of Bakelite waste in concrete mixtures generally leads to a decrease in compressive and split tensile strength, with the exception of the mixture containing 6 % Bakelite, which showed increased strength. Although there is a slight reduction in flexural strength, Bakelite waste prevents sudden specimen breakage and maintains specimen integrity. The ultimate load capacity of reinforced concrete beams with Bakelite waste is generally lower compared to the control beam, except for the 8 % waste Bakelite beam which demonstrated a similar ultimate load capacity of 60 kN. Although managing Bakelite waste can be difficult because it can lead to the creation of microplastics in landfills over time, utilizing Bakelite waste in concrete can be a sustainable method of waste management. The innovative use of Bakelite waste as a partial replacement for coarse aggregate in concrete offers a sustainable solution to the problem of waste management and addresses the environmental concerns related to the disposal of non-biodegradable plastics. This research provides a practical solution for developing eco-friendly and cost-effective construction materials while promoting sustainable waste management practices.

Long-term loss of tension stiffening of concrete containing recycled aggregate and steel fibres

This paper presents experimental results on the long-term loss of tension stiffening of concrete containing recycled aggregate and steel fibres. Washed construction and demolition wastes (CDW) size 20 mm were used as a replacement for the natural coarse aggregate, and hooked-end steel fibres (DRAMIX 3D 65/35BG) were added to the mixes. Square section prisms of concrete (120x120x1200 mm) reinforced with a central steel bar were prepared and cast with different replacement percentages of recycled aggregate and volume fractions of steel fibres. A direct tensile load was applied to the steel bar and the measurements of the strain on the concrete surfaces were then recorded for a period of 35 days to assess the long-term loss of tension stiffening. The results indicated that the substitution of NA by RA increased the loss of tension stiffening over time up to 12.9%. However, the addition of steel fibres proved to be highly beneficial; the inclusion of 0.5% and 1.0% steel fibre content to the NC and RAC reduced the loss up to 9.8% and 20.4%, respectively. According to the obtained results, modifications to the Eurocode2 method for predicting the long-term deflection of reinforced concrete beams were proposed to be implicated in the calculation steps for this type of concrete.

A sustainable reuse of e waste as a partial replacement material for aggregate

About 10 percent of E-Waste is produced in India annually. The present study is to utilize the E-Waste or Electronic waste such as circuit board waste, wires, and cables as a substitute for Coarse Aggregate (CA) and Fine Aggregate (FA). Since much of the waste are dumped into the soil grounds causes contamination of ground water, so it disturbs the plant growth and human health cycle. The waste can be utilized as much as possible to make a sustainable environment. Different combinations of about 5, 10 and 20% of the waste were much included as the substitute for FA and 10% as for CA. The samples are tested for specific gravity, consistency, compression testing, flexural strength, and split tensile strength. The results obtained serve as a feasible solution for E-management waste. Beyond 10% replacement of both coarse and fine aggregate the strength reduces than the required strength.

To Study the Properties of Concrete Mix on Partial Replacement of Coarse Aggregate with Burnt Bricks

These days, materials such as over-burned bricks blast are employed as an alternative to coarse aggregates. This paper investigates the physical features of concrete formed with burned bricks blast. Natural rock is by far the most common coarse aggregate used in concrete, however not all types of rock appropriate for concrete production are available everywhere. Due to a paucity of aggregate from natural sources in India's north-eastern states, brick aggregate concrete is commonly utilised for ordinary concrete. Due to advancements in concrete technology and to meet the requirements for durability, As a result of the need to utilise standard concrete, which only uses stone aggregate, construction costs have increased as materials are carried from other states. Making good quality concrete with the finest sand (grading zone – IV as per Indian code IS:383-1970) is difficult enough, but the natural coarse aggregate is scarce locally. Burnt brick aggregate has a high-water absorption rate (12 to 20% by mass), which makes it difficult to utilise in practical work. As a result, an attempt has been made to provide a viable solution for real-world use. To test various strength characteristics, an experimental investigation was done. In our project, waste material was employed as a coarse aggregate while simultaneously keeping the strength of the concrete. The effects of a percentage replacement of stone aggregates with burn brick aggregates on the compressive strength of concrete are presented in this study. Concrete cubes of M25 grade samples containing various percentages of brick aggregate, such as 0%, 10%, 20%, and 30%, are made 7-, 14-, and 28-days tests were performed.

A state-of-the-art review - mechanical properties of light weight concrete by utilizing sintered fly ash aggregate

Utilization of concrete increases rapidly which led to depletion of natural resources. In order to resolve problem on scarcity of coarse aggregate, various artificial aggregate material can be partially replaced in coarse aggregate like sintered fly ash aggregate, palm kernel shell or coconut shell can reduce disposal problems. Harmful effect of concrete can be reduced by iterate structural efficiency and its performance characteristics of concrete. Present findings focuses on feasibility of making structural light weight concrete using sintered fly ash aggregate and researches on use of sintered fly ash aggregate and other material as partial replacement of coarse aggregate for producing light weight concrete. According to a literature review, these aggregates are 16–46% lighter and more capable of absorbing water than aggregates of similar weight. The concrete produced using sintered fly ash demonstrated strong mechanical and structural qualities. Sintered fly ash aggregate concrete has compressive strength between 22 and 43 MPa and densities between 1600 and 2000 kg/m3. Concrete made using fly ash aggregate appears to function well in structural applications. Concrete using sintered fly ash aggregate has been considered as a possible structural concrete material.

Properties of concrete mixes containing tire rubber and brick powder exposed to sulfuric acid and cured in water: A comparative study

The existing literature shows that rubberised concrete suffers from reduced mechanical properties when it is compared with normal density non-rubberised concrete. This is due to the underlying reduced bonding between tire rubber and other concrete ingredients. The massive sulfuric acid attack in rubberised concrete must have additionally discouraged researchers from attempts to assess the phenomenon of improving performance of rubberised concrete. A research was undertaken to compare the properties of concrete mixes containing tire rubber replacing coarse aggregate and waste clay brick powder (WCBP) replacing cement exposed to sulfuric acid and cured in water. Concrete cubes and cylinders of concrete grades of 20 MPa, 25 MPa and 30 MPa were immersed in 5% sulfuric acid solution up to 90 days following moist curing of 27 days. Other concrete cubes and cylinders were cured in water for comparison. The compressive strength findings indicated that all the specimens exposed to sulfuric acid had lost more than 57% of their compressive strengths after 90 days with reference to the corresponding samples cured in water. In contrast, out of all concrete mixes investigated for all concrete grades, never were the split tensile strength losses of the specimens exposed to sulfuric acid greater than 43.1% compared with those cured in water. In each exposure condition, concrete mixes with 5% WCBP showed slight improvements in compressive and split tensile strengths in contrast with the conventional concrete mixes. Visual inspection of the specimens illustrated depositions of flaky or white substances on the outer layers of specimens exposed to sulfuric acid compared with specimens cured in water. Moreover, the split tensile strengths of specimens were not severely affected with exposure to sulfuric acid in comparison with compressive strengths. Eventually, the research identified the existence of WCBP in rubberised concrete as a promising criterion of minimising strength losses of rubberised concrete.

Optimization of plastic waste integration in cement bricks

Implementing plastic waste in construction materials is a sustainable disposal method to overcome plastic pollution. The current study aims to optimize the integration of plastic waste in cement bricks regarding their thermomechanical properties in order to develop an eco-friendly building material. Polyethylene terephthalate (PET) and high-density polyethylene (HDPE) partially substituted cement with different ratios (0, 2.5, 5, 7.5, 10, 20%). The type that achieved better thermomechanical performance further replaced the other brick components; sand and coarse aggregates to determine the optimum replacement scenario and best design mix. Laboratory experiments have been carried out to measure the compressive strength, indirect tensile strength, bulk density, and thermal conductivity of the new composites. The measured results revealed better performance for the samples with HDPE than PET. A boost in the compressive strength and indirect tensile strength was noticed for the samples obtaining a limited amount (up to 7.5%) of HDPE. However, a reduction in the tested mechanical properties occurs with higher substitution levels. With respect to thermal conductivity and bulk density, they decreased with the increase of plastic waste. The best mechanical behavior and the highest thermal resistance were obtained by partial replacement of coarse aggregates with 7.5% and 20% HDPE respectively. The results represent a good contribution to energy conservation, waste management and sustainability.

Effects of Partial Replacement of Sand by Crushed E-Waste on Mechanical Properties of Concrete

Abstract: Electronic waste is an increasing issue and a serious pollution problem for the environment and human life. The disposal of electronic waste is becoming a serious problem. The main potential for addressing the disposal of large amounts of electronic waste material is in the construction industry. The excess cost of coarse aggregate has forced civil engineers to find out an alternative solution for the construction materials. So, we can use e-waste as a partial replacement for coarse aggregate. Using electronic waste in construction will not only reduce the waste materials like electronic waste from the earth but also reduce the construction material(concrete) that will lead to economic construction. for Concrete mixes, different rate percentages of E-waste were selected and three different types of conventional and standard specimens have been decided to be partly replaced by E-waste at a percentage rate of 10%, 20%, and 30% for a coarse aggregate. M25 Concrete is usually prepared for conventional specimens without using E-waste aggregates. The results and effectiveness of concrete with e-waste replacement and the physical and mechanical properties of the following have been studied in this paper.

Partial Replacement of Coarse Aggregates with Plastic Waste in Paver Blocks

Plastics are widely used worldwide, but their non-biodegradable nature leads to significant waste generation. Improper management of plastic waste poses environmental hazards. Paver blocks made of concrete offer versatility, aesthetic appeal, and low maintenance when manufactured and placed correctly. Utilizing plastic as a building material aligns with Sustainable Development Goals. Concrete production contributes to the depletion of natural resources like aggregates. This study investigates the partial replacement of coarse aggregates with plastic waste in pavement blocks, using a mix ratio of 1:2:4. Coarse aggregates were replaced at volumes of 0%, 5%, 10%, and 15%. After batching and mixing, 54 cubes were produced and cured for 7, 14, and 28 days. Tests conducted included slump, compressive strength, and water absorption. The results indicate an optimal replacement of 10% of coarse aggregates with plastic waste which reduced water absorption. Plastic waste is recommended for use in low-load bearing walls and structures like pedestrian footpaths and water retaining structures, reducing costs and conserving natural resources. Effective utilization of plastic waste in the construction industry benefits the environment.

High-performance self-compacting concrete with recycled coarse aggregate: comprehensive systematic review on mix design parameters

ABSTRACT The technological advancements and environmental concerns enlighten the importance of incorporating more high-performance engineered materials in the construction sector. The partial replacement of natural coarse aggregates (NCA) with recycled coarse aggregates (RCA) in concrete has recently been a primary focus of worldwide researchers for sustainability in environmental aspects. The primary purpose of this review is to comprehend the effect of design parameters in determining the mechanical characteristics of high-performance self-compacting (HP-SCC) that include recycled coarse aggregates (RCA). Seven design parameters were extracted and considered in this review. It has been revealed that the design parameters of HP-SCC with RCA have a different effect on the mechanical characteristics of HP-SCC with various grades. In addition, the current research aims to promote environmental-friendly development and produce sustainable materials to improve mechanical-related characteristics in concrete in the absence of a precise evaluation technique. Artificial neural network (ANN) models have been implemented using the design parameters for predicting concrete mechanical properties based on three statistical indicators. The ANN-based model was attributed using these seven inputs of the literature with the help of sensitivity analysis for indicating the most critical design parameter HP-SCC.

Mechanical performance of steel tubes filled with demolished concrete lumps under axial compression

Demolished concrete lumps (DCLs) have been introduced as partial coarse aggregate replacements in concrete casting process. However, limited research works have been performed on sensitive behaviors of slenderness concrete filled steel tube (CFST) filled with fresh concrete (FC) and DCLs under axial compression. Based on the previous research work, orthogonal design method was employed to investigate further mechanical performance. Experimental studied involved 12 columns of CFST with diameter 159 mm and lengths 2000, 2200 and 2400 mm. The ratios of the diameter-to-thickness (D/t) were 79, 53 and 40, while replacement ratios of FC in DCLs were 0%, 20%, 40% and 60%, respectively. The results of experimental tests of the CFST filled with DCLs and FC indicated that ratio of slenderness have a greatest effect on the bearing capacity of slender column under axial compression, followed by the D/t ratio, and the weakest effect was observed for DCLs replacement. DCLs slightly affected the mechanical performances of slender CFST columns, so the ultimate bearing capacity of CFST can ignore the influence of replacement rate of DCLs. To calculate CFST slender column ultimate bearing capacity with DCLs, design codes AIJ, AISC, CE4, CECS 28: 2012, DL/T 5085-1999 were used to predicted ultimate bearing capacity, found that the code CECS 28:2012 was employed for the calculation of slender CFST DCLs filled column bearing capacity under axial compression being comparable accuracy.