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This study conducted an extensive literature review on rice husk ash (RHA), with a focus on its particle properties and their effects on the fresh, mechanical, and durability properties of concrete when used as a partial cement replacement. The pozzolanic property of RHA is determined by its amorphous silica content, specific surface area, and particle fineness, which can be improved by using controlled combustion and grinding for use in concrete. RHA particle microstructures are typically irregular in shape, with porous structures on the surface, non-uniform in dispersion, and discrete throughout. Because RHA has a finer particle size than cement, the RHA blended cement concrete performs well in terms of fresh properties (workability, consistency, and setting time). Due to the involvement of amorphous silica reactions, the mechanical properties (compressive, tensile, and flexural strength) of RHA-containing concrete increase with increasing RHA content up to a certain optimum level. Furthermore, the use of RHA improved the durability properties of concrete (water absorption, chloride resistance, corrosion resistance, and sulphate resistance). RHA has the potential to replace cement by up to 10% to 20% without compromising the concrete performance due to its high pozzolanic properties. The use of RHA as a partial cement replacement in concrete can thus provide additional environmental benefits, such as resource conservation and agricultural waste management, while also contributing to a circular economy in the construction industry.

The disposal of the huge volume of glass waste is one of the significant environmental issues that need to be addressed. One of the efficient ways to solve this problem is to incorporate ground glass waste in concrete mixtures. However, its inherent surface smoothness and microcracks within the glass particle harm the hardened properties of concrete. Minimizing the particle size and controlling the amount of cement in the mixture can reduce the adverse effect of using glass in concrete. This study utilized ground glass waste (850 μm) as aggregate filler in a concrete mix. More specifically, this study investigated the effect of paste volume (Vp) on the properties of fresh and hardened concrete with ground glass waste as aggregate filler. Based on the test results, ground glass waste as aggregate filler negatively affects the workability of fresh concrete, but increasing the amount of paste can mitigate it. Vp values in terms of void volume (Vv) in the aggregates of 1.6Vv and 1.8Vv achieved satisfactory consistency of fresh concrete. In addition, the concrete compressive strength increased when increasing Vp. The test results have shown that ground glass waste has the potential to be utilized as aggregate filler in concrete mixtures.

The concrete industry consumes a significant number of natural resources and emits hazardous gases into the atmosphere, such as carbon dioxide for cement production, which influences global warming and climate change. Therefore, many attempts have been made to develop green and eco-friendly concrete from various waste materials. Seashells are one of these waste products that accumulate on beaches and landfills, which causes environmental problems. This review assesses the usage of multiple types of seashell waste materials in concrete as a partial cement replacement. The performance of seashell powder in concrete was also evaluated in terms of fresh concrete properties, mechanical properties, durability, and other factors. According to this study, using seashells as a cement replacement improves concrete setting time, diminishes workability, and increases density due to curing age. The mechanical properties of concrete, such as compressive strength and modulus of elasticity, generally decrease as the shell content increases. However, adding admixtures and applying chemical treatment can improve concrete’s mechanical properties and durability. Nevertheless, adding up to 25% of cockle shells in concrete can reduce water permeability. Thus, it is demonstrated that using seashells in concrete as a cement replacement might have the potential to produce sustainable green building materials.

The properties and compressive strength of hardened concrete are examined by destructive and non-destructive testing methods. There was no direct relationship between non-destructive testing results for existing concrete structures. This article describes the comparison between rebound and compression hammer tests of hardened concrete. It also describes the comparison of strength and cube compressive strength as well as the comparison of modulus of elasticity according to different standards.Destructive and non-destructive techniques were used in an experimental programme on various concrete mixtures, including M20, M25, and M30. A comprehensive technique was used for evaluating the compressive strength properties of concrete grades M20, M25, and M30, using both destructive and non-destructive testing methods. The impact strength, maximum load, Schmidt hammer, and uniaxial compression test findings have been also reviewed within the examination. The study’s primary purpose was to clarify the connections between specific evaluations technique and actual grades. Similarly, those connections were subjected to an in-depth validation technique using previously advanced formulation from previous research, which produced precious statistics about the assessment of concrete strength. These findings increase our understanding of concrete’s behaviour and provide essential path for destiny packages inside the engineering and construction industries, enabling properly-informed decision-making in those domains.

The quest for eco-sustainable binders like agro-wastes in concrete to reduce the carbon footprint caused by cement production has been ongoing among researchers recently. The application of agro-waste-based cementitious materials in binary concrete has been said to improve concrete performance lately. Coconut and groundnut shells are available in abundant quantities and disposed of as waste in many world regions. Therefore, the use of coconut shell ash (CSA) and groundnut shell ash (GSA) in a ternary blend provides synergistic benefits with Portland cement (PC) and may be sustainably utilized in concrete as ternary cementitious material (TCM). Therefore, this study presents concrete performance with CSA and GSA in a grade 30 ternary concrete. Two hundred ten numbers of standard concrete samples were cast for checking the fresh and mechanical properties of concrete at curing ages of 7, 28, and 90 days. After 28-day curing, the experimental results show an increment in compressive, tensile, and flexural strength by 11.62%, 8.39%, and 9.46% at 10% TCM cement replacement, respectively. The concrete density and permeability coefficient reduce as TCM’s content increases. The modulus of elasticity after 90 days improved with the addition of TCM. The concrete’s sustainability assessment indicated that the emitted carbon for concrete decreased by around 16% using 20% TCM in concrete. However, the workability of fresh concrete declines as TCM content increases.

Concrete is a composite material that is commonly used in the construction industry. It will certainly be exposed to fires of varying intensities when used in buildings and industries. The major goal of this article was to look into the influence of mineral additions such as foundry sand and marble dust on the residual characteristics of concrete. To examine the behavior of residual characteristics of concrete after fire exposure, marble dust was substituted for cement and fine sand was substituted for foundry sand in varying amounts ranging from 0% to 20%. It aided in the better disposal of waste material so that it might be used as an addition. The purpose of the experiment was to see how increased temperatures affected residual properties of concrete, including flexural strength, compressive strength, tensile strength, static as well as dynamic elastic modulus, water absorption, mass loss, and ultrasonic pulse velocity. At temperatures of 200 °C, 400 °C, 600 °C, 800 °C, and 1000 °C, the typical fire exposure behavior of concrete was investigated. The effects of two cooling techniques, annealing and quenching, on the residual properties of concrete after exposure to high temperatures were investigated in this study. Replacement of up to 10% of the cement with marble dust and fine sand with foundry sand when concrete is exposed to temperatures up to 400 °C does not influence the behavior of concrete. At temperatures above 400 °C, however, the breakdown of concrete, which includes marble dust and foundry sand, causes a rapid deterioration in the residual properties of concrete, primarily for replacement of more than 10%.

Studies have explored the engineering properties of Polyethylene Terephthalate (PET) fiber-reinforced concrete, including mechanical strength, crack control, and durability. However, a comprehensive analysis incorporating surface treatment is lacking. This paper provides an extensive analytical database, including previous literature on the mechanical and durability properties of PET fiber-reinforced concrete and the effects of fiber surface treatment on concrete performance. Furthermore, the microstructural and pore-structural properties of PET fiber-reinforced concrete are discussed, detailing the mechanisms behind these properties. This examines the effect of incorporating virgin and recycled PET fibers at mass percentages (wt%) of 0–2 and volume percentage (v%) of 0–12 of total mass/volume. Key findings include that the optimum PET fiber content for tensile and flexural strength is 0.5 v%, while higher contents cause fiber balling, reducing concrete’s performance. Notably, PET fiber-reinforced concrete shows a maximum compressive strength loss of 24% in 3% H 2 SO 4 and 10% loss in pH 12.6 alkaline medium after 120 days. Surface treatment with 20 wt% NaOH and Silane improves compressive strength from 54 to 60 MPa. PET fiber coating with Graphene-oxide and Polydopamine increases frictional and chemical bonding in concrete by 85 and 70%, respectively. The study concludes that surface treatments enhance concrete properties by improving bonding and minimizing fiber degradation.

With the continuous improvement in technology, the construction industry is constantly advancing. Traditional concrete can no longer meet modern market demands, making research on new types of concrete imperative. This study reviews the application of common nanomaterials in concrete and their impact on concrete performance. It provides a detailed explanation of the characteristics of three common nanomaterials: nano-silica, nano-calcium carbonate, and carbon nanotubes. This study analyzes how these materials improve the microstructure, accelerate hydration reactions, and enhance interfacial transition zones, thereby enhancing the mechanical properties, durability, and workability of concrete. For conventional engineering projects, nano-calcium carbonate is the preferred choice owing to its low cost and its capacity to improve workability and early-age strength. For high-strength and durable structures, nano-silica is selected due to its high specific surface area (ranging from 100 to 800 m2/g) and its superior compactness and impermeability. In the context of intelligent buildings, carbon nanotubes are the most suitable option because of their exceptional thermal conductivity and electrical conductivity (with axial thermal conductivity reaching 2000–6000 W/m*K and electrical conductivity ranging from 103 to 106 S/cm). However, it should be noted that carbon nanotubes are the most expensive among the three materials. Additionally, this study discusses the issues and challenges currently faced by the application of nanomaterials in concrete and looks ahead to future research directions, aiming to provide a reference for further research and engineering applications of nanomaterials in the field of concrete.

The world is facing a huge problem of waste generation; among these, solid waste in the form of glass has become a prime concern for the environment. The composition of the glass is silica-based, and its utilization in the preparation of concrete can be an efficient step in the direction of sustainable development by reducing the cement content. The formation of secondary calcium silicate hydrates (C-S-H) could take place due to the pozzolanic reaction of the fine ground glass with the cement. TGA techniques were used in this research to investigate the chemical properties of the waste glass, and later, these were compared with the properties of the cement. By keeping a constant w/b ratio for all the replacement levels from 0% to 35%, the evaluation of the workability and compressive strength were done. The evaluation showed that workability increased with an increase in the content of the waste glass. With 7 and 28 days cured samples, the strength and chemical investigation were conducted on the samples prepared with the same mix design. Constant Dose of superplasticizer used by weight of cement for mixes as 0.8%. Compared with the control sample, The level of replacement of waste glass to cement as 30% has depicted the augmentation in the compressive strength. Thus, the use of waste glass was found to be cost-effective and an environment-friendly solution for the sustainable development of concrete.

Increasing the degree of digitisation and automation in the concrete production process can play a crucial role in reducing the CO2 emissions that are associated with the production of concrete. In this paper, a method is presented that makes it possible to predict the properties of fresh concrete during the mixing process based on stereoscopic image sequences of the concretes flow behaviour. A Convolutional Neural Network (CNN) is used for the prediction, which receives the images supported by information on the mix design as input. In addition, the network receives temporal information in the form of the time difference between the time at which the images are taken and the time at which the reference values of the concretes are carried out. With this temporal information, the network implicitly learns the time-dependent behaviour of the concretes properties. The network predicts the slump flow diameter, the yield stress and the plastic viscosity. The time-dependent prediction potentially opens up the pathway to determine the temporal development of the fresh concrete properties already during mixing. This provides a huge advantage for the concrete industry. As a result, countermeasures can be taken in a timely manner. It is shown that an approach based on depth and optical flow images, supported by information of the mix design, achieves the best results.