Partial Replacement Of Sand Research Articles

Feasibility of recycling autoclaved aerated concrete waste for partial sand replacement in mortar

The study aims to examine the feasibility of recycling autoclaved aerated concrete waste (AACW) on a vast scale to prepare sustainable mortars without large mechanical strength reduction. The recycled AACW was utilized as fine aggregate to partially replace natural river sand in mortar with various replacement levels and particle sizes. The physical properties and mechanical strength of prepared mortars were investigated experimentally. The internal curing effect of the AACW and the interfacial transition zone between recycled fine aggregate and cement paste were characterized from microstructural perspectives. Results indicate that the incorporation of AACW decreased the density and increased water absorption and voids volume of mortar. At a particle size of 0.15–0.3 mm, the higher compressive and flexural strength of mortars were observed and AACW can successfully be recycled into fine aggregate to replace up to 50% of the river sand in mortar. The internal curing effect of AACW improves the hydration of investigated mortars, and the increased crystalized calcium-silicate-hydrate is conducive to enhancing the mechanical strength of mortars. Furthermore, the backscatter scanning electron images demonstrate that the internal curing effect of AACW reduces the formation of cracks in the recycled fine aggregate/cement paste interfacial transition zone. The findings of the present work can provide a guidance for recycling AACW into fine aggregate on a vast scale to prepare sustainable mortar.

Partial Replacement of Sand in Concrete with Available Natural Pozzolan in KSA

This paper presents an experimental investigation on the effect of the partial replacement of fine aggregates in concrete with available local Natural Pozzolan (NP) in Al-Madinah Al-Munawarah, Kingdom of Saudi Arabia (KSA). The utilization of NP has reduced the density of concrete and improved its mechanical properties. The Saudi Building Code has recommended using pozzolan with a special type of cement in the case of concrete exposed to high percentages of sulfate. 48 concrete cylinders with dimensions of 150×300 mm have been prepared. The cylinders have been divided into two groups according to the level of cement replacement with Silica Fume (SF). The first group consists of 24 concrete cylinders with Natural Sand (NS) substitution with NP by volume at replacement levels of 20%, 50% and 100% without SF. The second group consists of 24 concrete cylinders with sand substitution with NP by volume at replacement levels of 20%, 50% and 100% in addition to the presence of 5% cement replacement by weight with SF. The concrete cylinders have been tested after 28 days. The utilization of NP and SF has showed a noticeable influence on the mechanical properties of concrete. Therefore, based on the results, the replacement of 20% of fine aggregate and 5% of cement in concrete with NP and SF, respectively has increased the compressive and tensile strength of concrete.

RSM and ANN modelling of the mechanical properties of self-compacting concrete with silica fume and plastic waste as partial constituent replacement

In this study, Response Surface Methodology (RSM) and Artificial Neural Networks (ANN) was used to predict the mechanical properties of self-compacting concrete (SCC) with silica fume as partial cement replacement and Polyethylene terephthalate (PET) solid waste as partial sand replacement. PET plastic was varied between 0 and 20 wt% while the silica fume was varied between 0 and 40 wt%. The parameters investigated were the compressive strength, tensile strength and impact strength of SCC. The RSM model was fairly accurate (R2 ≥ 0.92) in predicting the mechanical properties. The model was statistically significant (p-value < 0.5) and did not possess any prediction bias. The ANN model was able to capture the variability of the data as evidenced by the good R2 threshold (R2 > 0.93) for training, testing and validation. Parity plots revealed that both the ANN and RSM models do not have any prediction bias. However, the ANN model is superior because of its higher accuracy and the use of admixtures enhanced the workability suitability for dataset. The 3D microstructural analysis showed that the interfacial adhesion between the aggregates and the cementitious materials reduced at increased partial replacement leading to a decrease in the strength.

Development of an environmental-friendly durable self-compacting concrete.

In this experimental study on self-compacting concrete (SCC), the Manufactured sand (M-sand) and Fly ash (FA) were utilised for partial replacement of Natural sand (N-sand) and Ordinary Portland Cement (OPC), respectively. N-sand was partially replaced by M-sand at various percentage levels, after the dose of FA in the mix was optimised. In terms of compressive strength, the optimum replacement level of OPC by FA was 20%, whilst for replacement of N-sand by M-sand it was 50%. Two types of mixes were prepared to compare the macro and micro level properties of SCC, i.e., SCC-I (100%OPC + 100%N-sand) and SCC-II (80%OPC + 20%FA + 50%N-sand + 50%M-sand). The characteristics of fresh concrete mixes were determined using Slump flow, T50 time, V-funnel, L-box, U-box, and J-ring tests. After 28days of curing in tap water, both types of specimens were exposed to a solution of ammonium sulphate [(NH4)2SO4] containing sulphate salt concentration of 2.0g/l for 360days to test their durability. Loss in compressive strength, weight change, sorptivity, and micro-structural changes (XRD, SEM, and EDS) all were evaluated for up to 360days. It was found that the use of FA and M-sand in concrete makes it more environmental-friendly and durable, as well as have better performance in a sulphate environment.

Compressive Strength of Palm Oil Lightweight Aggregate Concrete Containing Industrial Waste as Partial Sand Replacement

Palm oil fuel ash (POFA) and palm oil clinker (POC) are by-products from palm oil mill which disposed as environmental polluting wastes. Excessive sand mining activity by sand traders for the widely used concrete production, harms the river’s ecosystem. Success in discovering alternative material that can function as partial sand replacement for concrete production would reduce the dependency on natural sand supply. This research investigates the effect of POFA as a partial fine aggregate substitute on the workability and compressive strength of palm oil clinker lightweight aggregate concrete. Five mixes have been prepared by integrating diverse percentage of POFA ranging from 0, 5, 10, 15 and 20 as fine aggregate substitute by weight of sand. Then, concrete mixes were subjected to slump test and compressive strength test. The outcomes have shown the combination of 5% POFA in this lightweight aggregate concrete produces concrete with the targeted strength and has the potential to be used for structural application. Utilization of POFA in concrete would save the consumption of river sand and contribute to sustainable environment.

Thermal energy storage cement mortar containing encapsulated hydrated salt/fly ash cenosphere phase change material: Thermo-mechanical properties and energy saving analysis

Solar passive house equipped with thermal energy storage cement mortar (TESCM) containing encapsulated phase change material (PCM) has showed great potential in terms of energy saving. However, TESCMs are universally behaved as deteriorated mechanical strength and high cost, limiting their applications. This study developed a novel TESCM by integrating cement mortar with polyethylene glycol@SiO2-coated eutectic hydrated salt/fly ash cenosphere encapsulated PCM, in order to improve the mechanical property and cost-effectiveness. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and attenuated total reflection Fourier transform infrared (ATR-FTIR) results showed that the synthetic encapsulated PCM possessed satisfying encapsulation ability, latent heat and chemical compatibility. The encapsulated PCM was incorporated into cement mortar by partial replacement of sand. It turned out that the prepared TESCM containing 20% encapsulated PCM exhibited 28d compressive and flexural strengths of 36.5 MPa and 6.2 MPa, merely presenting slight decreases of mechanical strengths compared to the control cement mortar. Moreover, X-ray diffraction (XRD), thermal gravimetric (TG) and backscattered electron (BSE) were conducted on TESCM to analyze the hydration products, hydration degree and interface transition zone between cement matrix and the encapsulated PCM, and the influence on mechanical strength was deeply analyzed. Besides, thermal performance test confirmed that the prepared TESCMs had good heat storage capacity. In the heating test, the peak temperature in the test chamber equipped with TESCM was reduced by 3.1 °C when 20% encapsulated PCM was contained in TESCM. Furthermore, economic evaluation indicated the low cost and prominent energy saving performance of the prepared TESCM. This work provides insights into the developing structural-functional building materials with high mechanical strength and thermal energy storage for efficient solar energy utilization in passive buildings.

Compressive Strength of Lightweight Aggregate Concrete Containing Crushed Cockle Shell as Partial Sand Replacement

The widespread use of natural sand mined from the river for concrete production worldwide causes environmental degradation. The cockle shell waste from aquaculture industry which discarded at dumpsite also pollutes the environment. Utilization of cockle shell as partial sand replacement in concrete would reduce the harvesting of sand from the river and limit the waste dumping from cockle industry. The experimental research investigates the effect of different sizes crushed cockle shell (600µm and 2.36mm) as partial sand replacement on the workability and compressive strength of lightweight aggregate concrete. 5 types of concrete mixes consisting various percentages of crushed cockle shell ranging from 0%, 5%, 10%, 15% and 20% were used in this research. All specimens were water cured until the scheduled testing time. The workability and compressive strength of concrete were determined via slump test and compressive strength test respectively. The outcome shows that the use of different sized crushed cockle shell as partial sand replacement influences the workability and strength of concrete. The concrete becomes more workable when larger quantity of crushed cockle shell is used. Integration 5% of 600µm and 10% of 2.36mm crushed cockle shell forms concrete with the targeted strength. Using crushed cockle shell as mixing ingredient in concrete reduces quantity of waste thrown and contributes to cleaner surrounding.

Effect of Coal Bottom Ash as Partial Sand Replacement for Lightweight Aggregate Concrete

Environmental degradation due to disposal of waste namely coal bottom ash waste from thermal power plant, clinker waste of palm oil mill and river sand mining activity for concrete production need to be resolved. Palm oil clinker lightweight concrete with zero granite aggregate that been produced in effort to reduce dependency of natural stone consumption has been further explored its potential in this research. Thus, the present research investigates the compressive strength, water absorption and acid resistance of lightweight aggregate concrete containing coal bottom ash as partial sand replacement. Five types of concrete mixes were produced using 0%, 10%, 20%, 30% and 40% coal bottom ash as fine aggregate replacement. After curing process, specimens were immersed in acid hydrochloric solution before subjected to compressive strength testing. Findings show that all specimen experience strength reduction after exposed to acidic environment. On overall, the use of coal bottom ash influences the durability performance of lightweight aggregate concrete.

Properties of High-Density Ultrahigh-Performance Concrete Containing Hematite Powder as a Partial Replacement of Sand

Properties of High-Density Ultrahigh-Performance Concrete Containing Hematite Powder as a Partial Replacement of Sand

Feasibility study of palm oil boiler ash (POBA) as a partial replacement of sand in foamed concrete

A study was conducted to explore the effect of palm oil boiler ash (POBA) on foamed concrete by varying the percentage of POBA over sand quantities (0, 4, 8 and 12%). This paper primarily discusses the water absorption test, uniaxial compressive strength, and dry density findings. It indicates that substituting sand with POBA greatly enhances the strength of foamed concrete. When the quantity of POBA was raised up to 12% throughout all curing times, the compressive strength steadily increased in the range of 4.34–13.50 N·mm–2. Furthermore, the dry density of foamed concrete was shown to be directly related to the fraction of POBA in the mixture. The dry density of foamed concrete increases as the amount of POBA increases. Despite this, water absorption shown that increasing POBA increases water absorption percentage in foamed concrete from 7.4 to 10.4%. This is due to the fact that a composition with a high POBA percentage will generate more pores than a mixture with a low POBA percentage.

An Experimental Study on Effect of Bottom Ash as partial Replacement of Sand on Properties of Concrete

An Experimental Study on Effect of Bottom Ash as partial Replacement of Sand on Properties of Concrete

The Physical and Mechanical Properties of Autoclaved Aerated Concrete (AAC) with Recycled AAC as a Partial Replacement for Sand

The application of AAC has increased considerably in Malaysia since the 1990s. The usage of AAC has some advantages, but it also has negative environmental impacts since rejected concrete will become landfill. This study aimed to use AAC waste powder as a material that would partially replace the sand content to produce a new form of Autoclaved Aerated Concrete (AAC). The physical and mechanical properties of the newly developed AAC were investigated. This paper presents improved mechanical and physical properties of the new form of recycled AAC concrete. Besides these improvements, using recycled AAC could lower production costs. Furthermore, the usage of this recycled waste powder is both economically and environmentally advantageous. This study found that when recycled AAC was substituted for sand, AAC with a fine recycled powder content of 30% had a compressive strength that was around 16% higher than conventional AAC and between 29% and 156% higher than any value attained utilizing an industrial waste product. This study also confirmed that the greater strength could be identical to a higher tobermorite phase and that the recycled AAC surface showed a finer crystalline morphology.

Partial Replacement of Sand and Cement by Reinforced Rubber Powdered for Concrete Performancepartial Replacement of Sand and Cement by Reinforced Rubber Powdered for Concrete Performance

Partial Replacement of Sand and Cement by Reinforced Rubber Powdered for Concrete Performancepartial Replacement of Sand and Cement by Reinforced Rubber Powdered for Concrete Performance

Thermal conductivity and hardened behavior of eco-friendly concrete incorporating waste polypropylene as fine aggregate

Waste polypropylene is one of the most common non-biodegradable solid wastes generated by industrial activity in Iraq. Solid waste is one of the several causes having a negative effect on the environment. The issues arise as a result of factors such as the difficulty of recycling waste and restricted reuse. Polypropylene is a significant kind of solid waste that has a negative impact on the environment. The purpose of this study is to determine the effects of using polypropylene as a partial replacement for sand in concrete. This material's effect on the fresh, mechanical, and thermal conductivity properties of concrete was investigated. Six concrete mixtures using polypropylene as a partial substitute for sand were produced at substitution percentages of 0%, 8%, 16%, 24%, 32%, and 40%. The slump, fresh and dry unit weight, compressive strength, and thermal conductivity properties of fresh and hardened concrete were determined. At various rates of concrete production, the results of the experiments demonstrated a decrease in unit weight and compressive strength. Thermal conductivity reduced 49.1% for the mix contained 40% of waste polypropylene and satisfied the lower limit strength for structural purposes.

Concrete strength analysis using waste plastic as a partial replacement for sand

Plastic got its acceptance as an acceptable-durable material around the globe since late twentieth century. But gradually people understood the issues with plastic that it takes millennia to disintegrate and that this sluggish breakdown rate has a harmful impact on both ocean and terrestrial ecosystems. PET (poly-ethylene terephthalate) is a widely used plastic that is primarily utilized in the production of plastic containers and water bottles. The effect of incorporating carbonated PET plastic wastes into concrete as a fine aggregate alternative, in the achievable concrete strength is investigated in current study. The compressive strength of concrete was determined for five distinct samples with 1%, 2%, 3%, 4%, and 5% substitution of fine aggregates with squashed PET powder. Slump decreased with the enhancement of replacement proportion and binding strength between cement matrix and aggregates improved as the gap at the interfacial transition zone was minimized for all replacements. The unconfined compressive strength of concrete got a thrust. The optimum achievable results were obtained at 3% replacement level.

Experimental and finite element studies on the flexural behavior of optimized green concrete using GGBS and pond ash

In this paper, the flexural behavior of reinforced concrete (RC) beams developed using an optimized green concrete with pond ash (PA) and ground granulated blast furnace slag (GGBS) as a partial replacement for river sand and cement was studied. In total, 16 mixes were prepared by replacing cement using GGBS up to 50% and river sand by pond ash up to 30% in tandem. From the different mixes cast, an optimized green concrete mix with GGBS and pond ash was selected based on the performance of fresh (slump test) and hardened properties (compressive strength). The optimized mix with 30% GGBS and 20% pond ash was used further for understanding the flexural behavior of RC beams. In specific to this study, six RC beams were tested by varying shear span (a) to depth (d) ratios. In addition to the experimental study, a detailed three dimensional finite element analysis (FEA) was performed using the ABAQUS software and validated with the test results.

An experimental study on controlled low strength material (CLSM) for utilization as sustainable backfill

Disposal of ash produced by coal-based power plants is a global problem because of its fineness and lack of space for its pondage. In recent years, efforts have been made to reutilize ash for different applications, viz., manufacturing of cement, bricks, tiles, in concrete, for soil stabilization, construction material for roads and bridge abutments, etc. However, there is a need to find more applications for the complete utilization of ash. In this direction, the present work explores potential of fly ash and pond ash for development of controlled low strength material (CLSM), an alternative material for backfilling applications. The performance of different compositions of CLSM have been studied, by partially replacing sand and cement, with pond ash and fly ash, respectively. Experimental studies have been performed to obtain flowability, hardening time and compressive strength (soaked and unsoaked conditions) for different CLSM combinations. In the present study, 20% binder content and 80% filler content has been considered, with a water/binder (w/b) ratio of 1.7 based on initial trials. Further, variation in percentage of fly ash and pond ash as partial replacement of cement and sand, respectively, have been evaluated. From the test results, it can be concluded that upto 75% replacement of sand by pond ash (60% of overall mix) is possible for development of CLSM with desired properties. Furthermore, the 28-days average compressive strength observed for CLSM varies from 0.4 MPa to 1.8 MPa for the studied combinations. This range of strength is favourable for backfilling applications, wherein, excavation in future may be necessary. Though the study results are quite encouraging towards development of CLSM using pond ash and fly ash, further studies on durability properties and minimizing the variation in properties would help towards developing sustainable CLSM for environmentally friendly infrastructure development.

Investigation on Concrete with M-Sand and Silica Fume

The global construction industry uses a significant amount of concrete. In India, the ordinary concrete is created utilizing natural sand from river beds as fine aggregate. Because dwindling natural resources constitute an environmental risk, government restrictions on sand mining have led to a shortage and a sharp rise in the price of the material. The optimization of M-Sand with silica fume as a partial replacement for natural sand is discussed in this work. Compressive and split tensile strengths of concrete mixtures were assessed. Natural sand was substituted with manufactured sand in five proportions of 0, 10, 20, 30 and 40%, while silica fume was substituted for standard Portland cement in amounts of 0, 5, 7.5 and 12.5%. The findings showed that concrete with 30% M-Sand and 7.5% silica fume has increased compressive and split tensile strength.

Investigation on Mechanical and Durability Performance of Reinforced Concrete Containing Red Soil as Alternate for M‐Sand

The river sand is a primary parameter in the concrete structure. This work replaces accessible locally accessible substitution materials like red soil and manufactured sand (M‐Sand). In this paper, the mechanical properties and durability of concrete containing red soil and M‐Sand have been studied. In this investigation, M30 grade concrete was used, and tests were conducted for two sets of combinations; i.e., red soil as a partial replacement for river sand seems to be 20%, 30%, 40%, 50%, and 60%, and red soil as a partial replacement for manufactured sand (M‐Sand) seems to be 60%, 50%, 40%, 30%, and 20%. The compressive strength (7 days, 28 days, 90 days), split tensile strength (28 days), and flexural strength (28 days) have been determined. The combination S4‐50% river sand + 50% red soil and S9‐70% M‐Sand + 30% red soil gives more compressive strength than other combinations. Similarly, the combination S3‐60% river sand + 40% red soil and S6‐40% M‐Sand + 60% red soil gives more flexural and split tensile strength than other combinations. The scanning electron microscope (SEM) analysis, EDAX analysis, and durability tests like alkalinity, sulfate attack, and chloride attack have also been studied.

Evaluation of the durability of concretes associated with flash metakaolin or silica fume

This article reviews the effects of silica fume (SF) and metakaolin (Mk) properties on water accessible porosity, chloride ion diffusion, gas permeability and electrical resistivity. The concretes are tested with proportions of 15% and 20% of Mk and 5% and 10% of SF compared to the concretes without addition. Incorporation is based on a partial replacement of fine sand. A total of fifteen mixtures are made according to three different Water/Binder ratios: 0.50, 0.46 and 0.40. Durability indicators are evaluated for ages of 7, 28, 56 and 90 days. The incorporation of SF or Mk into cement matrices is intended to study the effect of the effective pozzolanic reaction which can improve the development of the concrete microstructure compared to control concretes. Therefore, the comparison of the tested concretes with addition shows a decrease in durability indicators as follows: (1) for porosity from 1% to 11% for SF and from 4% to 12% for Mk, (2) for the diffusion of chloride ions from 54% to 75% for SF and from 55% to 86% for Mk, (3) for gas permeability from 6% to 22% for SF and from 5% to 28% for Mk. Electrical resistivity, as well, shows an increase compared to the control mixture from 64% to 163% for SF and from 50% to 104% for Mk. A good correlation was observed between the compressive strength and the tested durability indicators of the different concretes.