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This research investigates reinforced concrete beams with three groups of Glass Fiber Reinforced Polymer (GFRP) bar, Sand-blasted Glass Fiber Reinforced Polymer (SGFRP) bar and steel bar with concrete containing recycled materials with different concrete mix design before and after applying elevated temperature. The concrete mix designs include replacing glass powder and micro-silica with a part of concrete cement and replacing waste crumb rubber and glass crumb with a part of fine and coarse concrete aggregate. The beams were subjected to high temperature up to 600 °C in an electric furnace, and then subjected to the flexural strength test. The results showed that applying elevated temperature to beams reinforced with composite bars caused a sharp drop in flexural strength. The beam exposed to high temperature containing glass powder, coarse rubber and micro-silica had 2.2 times more flexural strength than the reference beam exposed to high temperature, and the beam not exposed to high temperature in this mix had 36% more flexural strength and 54% more ductility than the reference beam that was not exposed to high temperature. The beam with SGFRP bar with sand coating showed higher flexural strength after applying elevated temperature than the beam with GFRP bar with normal surface. In general, the replacement of recycled materials in the concrete improved the performance of the beams against elevated temperature compared to the beams with normal concrete. [ABSTRACT FROM AUTHOR]

Reusing waste materials presents a significant challenge for researchers across the globe. One of the most prevalent waste materials found in all communities is waste glass, as it plays a substantial role in various aspects of human life. Numerous experiments have been conducted to incorporate waste glass as a raw material in concrete and mortar, serving as a replacement for components like coarse aggregate, sand, or even cement. The most efficient utilization of waste glass appears to be when it is used as a partial substitute for cement, primarily due to its contribution to the pozzolanic reaction and its ability to enhance the compressive strength of mortar and concrete. This article is dedicated to reviewing prior experimental work on the use of waste glass powder as a partial replacement for cement in mortar. These studies have demonstrated that the size and chemical composition of waste glass powder are crucial factors in determining its impact on various properties of mortar. Additionally, experimental data have been collected and employed to propose a statistical model for predicting the compressive strength of mortar, taking into account all independent variables that influence strength. Two modeling techniques, multi logistic linear regression (MLR) and artificial neural network (ANN), were compared, with ANN emerging as the more effective model. This conclusion is supported by the fact that ANN achieved an R-squared value 30% higher than that of MLR, and the performance indices (SI values) for both training and testing data were equal and below 0.1, indicating its superior predictive capability. [ABSTRACT FROM AUTHOR]

The study examines the impact of WGP on the resistance of mortar to sulfuric acid solution attack, with specimens containing 0%, 5%, 10%, 15%, 20%, 25%, and 30% WGP produced as cement substitutes. Some fundamental properties of mortar mixtures were evaluated, such as the pozzolanic activity index assessment, fresh density, water absorption, and compressive strengths during water curing times. Subsequently, the behavior characteristics of mortars when subjected to sulfuric acid solutions were assessed, including mass loss, residual compressive strength, visual inspection, and microstructure features during eight weeks of immersion in sulfuric acid. The results of the study indicated that the incorporation of WGP led to improved sulfuric acid resistance in the mortar. Furthermore, an increase in WGP content resulted in a reduced reduction in compressive strength against sulfuric acid attacks as the ages progressed. The study revealed that the mortar containing 5% WGP as a cement substitute had the highest compressive strength compared to other specimens, and using 10% WGP as a supplementary cementitious material was comparable to the control mixture. Finally, the microstructure tests indicated that the sample containing 5% WGP had a lower intensity of CH peaks than the reference sample. The study suggests that the optimum amount of GWP for strength and economic parameters is 5%, and 10% substitution, respectively. However, when considering acid solution resistance, 25% GWP cement replacement is the ideal content. [ABSTRACT FROM AUTHOR]

The substantial amount of CO2 emissions associated with the production of cement leads to an arising requisite for blending the cement with supplementary cementitious materials (SCMs). This study targets the production of a quaternary blended cement that exhibits the highest performance in terms of sustainability, mechanical and durability characteristics. Fly ash, glass powder and nanosilica of up to 30, 15 and 3%, respectively, were used in this study as SCMs. Dosages of the various SCMs used were optimized to maximize the 28th-day compressive strength and minimize chloride ion penetration, while minimizing the cement content using the response surface method. The ANOVA analysis showed high significance of the nanosilica and glass powder contents in determining the compressive strength, whereas fly ash content presumed insignificant effect on it. Fly ash, nanosilica and glass powder contents have been demonstrated significant in their effects on the resistance against chloride ions penetration. An optimal mixture containing 20% fly ash, 1.9% nanosilica and 15% glass powder as partial replacements of cement was found to have a sustainable concrete with the lowest cement content, 46.56 MPa of compressive strength and 688.98-C total chloride ion passing at 28-day age. [ABSTRACT FROM AUTHOR]

Influence of nano-glass powder on physico-mechanical properties of geopolymer composite materials has been studied, in addition to studying their firing stability against high temperature from 500 up to 1000 °C. For increasing mechanical, physical as well as firing stability for metakaolin composites; Nano-glass powder was used. Alumino-silicate materials are kaolin, fired kaolin (metakaolin) and limestone all pass 75 µm. Materials prepared at water/binder ratios in a range of 0.40; whereas the used activator 5 M sodium hydroxide with equal volume of liquid sodium silicate. Nano-glass powder added as a partial replacement for metakaolin material in the ratio of 1 up to 9%. Results indicated that compressive strengths of geopolymer mixes incorporating Nano glass powder were obviously higher than those of control one and increased up to 7% followed by slight decrease of on using 9%. Firing of hardened geopolymer results in high thermal resistance up to 500 °C then exposed to decrease up to 800 then increased again at 1000 °C for specimens incorporated 7 and 9% nano-glass powder. However, no micro-cracks were noticed up to 800 °C for all samples as recorded by visual examination of the fired samples. [ABSTRACT FROM AUTHOR]

Building structures can suffer from mechanical, physical and chemical pathologies. One of the serious hazards that can drastically reduce the service life of concrete structures is fire or high temperatures. The use of fine additive materials (FAM) can be a good way for enhancing the fire resistance of concrete. This paper aims to produce an eco-efficient and cheaper self-compacting mortar (SCM) that has a sufficient resistance to high temperatures, by replacing a part of cement with powders from recycled materials, such as glass and ceramic. Nine mixtures were prepared and tested, one as reference mix and eight containing, separately, different proportions in mass of ceramic and glass powders with 5, 15, 25 and 50%. In order to study the behavior of SCM at high temperatures, a total of 135 specimens of 40 × 40 × 160 mm were cast and left cured for 28 days and then subjected to different temperatures (400 °C, 600 °C, 800 °C and 1000 °C) for 2 h. The degradation was assessed by measuring the loss of mass, compressive strength, flexural strength and ultrasonic pulse velocity (UPV) for each temperature. Under conventional temperature, both of compressive and flexural strength and UPV decreased with introducing ceramic and glass powders. The optimal percentage use of ceramic and glass powders under fire conditions is 5%. This percentage can be increased to 15% or 25% to obtain SCM with acceptable mechanical and physical properties. The replacement of 50% of cement with glass powder caused a significant reduction in the mechanical performance of SCM mixture compared to ceramic powder at the same percentage. [ABSTRACT FROM AUTHOR]

Due to extremely dense microstructure, reactive powder concrete (RPC) shows poor performance at elevated temperatures owing to the development of high pore pressure that causes the deterioration of the material. By using fiber reinforcement, elevated temperature performance of RPC can be improved, as noted by many researchers. To this end, 3% volume fraction of four combinations of steel fiber (SF) and glass fiber (GF) [(3%, 0%), (2%, 1%), (1%, 2%), and (0%, 3%)] was used in RPC to study the change in residual mechanical properties of RPC after exposure to elevated temperatures. Three main mechanical properties, i.e., compressive strength, splitting tensile strength, and flexural strength properties, were studied. Experimental results showed that using 3% volume fraction of fibers (regardless of combination), explosive spalling of RPC was completely prevented. Hybrid fiber RPC with 2%SF–1%GF showed the maximum best mechanical performance at both elevated and normal temperatures. Single 3%SF–RPC performed significantly better than single 3%GF–RPC at both normal and elevated temperatures. A strong correlation existed between the normal temperature strength, residual strength, and exposure temperature. [ABSTRACT FROM AUTHOR]

Increasing concern over environmental issues has put onus on the construction industry to develop products and materials that are more sustainable and environmentally friendly. This paper focuses on the utilization of oil palm fibers (OPF) and glass powder (GP) to develop thermally efficient building material as a sustainable alternative. OPF are abundantly available in Malaysia as waste in palm oil manufacturing and are found to be useful in enhancing the thermal performance of building material , while waste glass, which contributes to municipal solid waste generation, can be beneficially utilized as a supplementary cementitious material as it possesses pozzolanic behavior. OPF-reinforced blocks were successfully developed with targeted thermal, mechanical and microstructural properties as a sustainable alternative for application in the hot–humid weather conditions in Malaysia. This paper reports on the development of the glass powder–fiber-reinforced mortar (GPFRM) as a final phase of the research in the development of a sustainable thermally efficient wall system. The GPFRM mix was prepared utilizing fibers in ratios of 0.5%, 1% and 1.5% by weight of the binder, whereas GP was incorporated by replacement of 10% and 20% of cement. The developed GPFRM besides having good thermal performance has acceptable mechanical performance, hence proving to be a sustainable alternative to conventional mortar to be incorporated within masonry wall systems. [ABSTRACT FROM AUTHOR]

This paper characterizes the sugarcane bagasse ash as a pozzolan and investigates its influence on the hardened properties of concrete. In Pakistan, the sugar industry recycles raw bagasse for power generation, and as a result, tonnes of bagasse ash are produced every year. For this study, the bagasse ash sample was obtained from one of the local sugar mills of Pakistan. The physical, chemical and mineralogical of bagasse ash were investigated by employing X-ray diffraction (XRD), X-ray fluorescence and laser particle size techniques, while the microstructure was studied through scanning electron microscope. In addition, the evaluation of hardened properties like compressive strength, tensile strength, flexural strength and thermal conductivity was also carried out. Here, the concrete mixtures were prepared by replacing the cement with bagasse ash in the ratio of 5 to 30% (by weight). The chemical, physical and mineral results reveal that this local bagasse ash has all pozzolanic properties. The evidence of amorphous and crystalline phases was found in the XRD pattern, along with silicon dioxide (SiO2) which was recorded more than 70% in the ash. It was observed that the workability for bagasse ash-blended concrete mixtures increases with ash content. Furthermore, the bagasse ash mixtures with 10% substitution were found optimal for achieving higher compressive, flexural and tensile strength, while the thermal conductivity showed a consistent drop with higher ash content percentage. [ABSTRACT FROM AUTHOR]

Road quality is one of the most important factors concerning the safety of transportation. Adequate skid resistance of a road surface allows drivers to maintain effective control on their vehicles and maneuver when necessary to avoid accidents. Using waste glass in asphalt mixtures is advantageous from the point of technical, environmental and economic perspectives. This study focuses on the topic of asphalt containing crushed glass, also known as glasphalt, by evaluating the skid resistance and moisture sensitivity of these mixtures. Therefore, a laboratory method was used, in which two types of continuous gradation of hot mix asphalt were chosen based on the Iranian highway asphalt paving code (Code No. 234). The fine aggregates, up to 15% of the total aggregate content, were replaced with glass particles in three different gradations. Skid resistance was evaluated in a British pendulum tester, moisture sensitivity by modified Lottman test, and resilient modulus in a UTM machine. Specimens with a moisture sensitivity problem were improved by using zycotherm as an anti-stripping agent. It was found that the crushed glass particles improved skid resistance by up to 20%. The moisture sensitivity test showed that some glasphalts were susceptible to stripping issue, which can be solved by using 0.1% zycotherm in terms of bitumen weight. Finally, findings revealed that glass particles improved resilient modulus of specimens. [ABSTRACT FROM AUTHOR]

The deep mixing has recently become a popular technique for improvement of weak or problematic soils in order to increase bearing capacity and reduce settlement. Despite various successful applications in construction projects, specifically improvement of marginal sand (i.e., loose poorly graded sand) using new materials in the viewpoint of strength development is still open for the attempt of deep mixing regarding the binder of grout, curing time and clay content. Thus, in this paper, effect of glass powder added to cement-based slurry grout in different proportions (0, 3, 6, 9% by dry weight of binder) has been experimentally investigated for deep mixing of marginal sand with various clay contents (4, 8, 20%). An experimental program has been developed for this purpose conducting the Vicat, unconfined compressive strength (UCS) and ultrasonic pulse velocity (UPV) tests for the performances of soilcrete samples. From the testing results, it is found that: (i) The glass powder is not able to accelerate the setting times of grout, (ii) the bulk density does not significantly change with the glass powder, clay content and curing time, (iii) the most performed UCS value is obtained due to the addition of 3% glass powder at the 28-day curing for the soilcrete samples of 20% clay content of sand, while all UCS magnitudes obtained for the soilcrete samples are considered acceptable for the construction of soil-cement column, (iv) the elastic modulus correlates well with the UCS values (R≥ 0.83) at the majority of soilcrete samples and (v) the UPV values of soilcrete samples at 28-day curing perform better due to the addition of 3% glass powder similar to the response trend of UCS, while their performances are higher due to 4% clay content in contrast to the trend of UCS. As a consequence, this study demonstrates the use of glass powder added grout to be beneficial for deep mixing of marginal sand, in which 20% clay inclusion contributes more. [ABSTRACT FROM AUTHOR]