Strength Properties Of Concrete Research Articles

A Comprehensive Review on Use of Wastewater in the Manufacturing of Concrete: Fostering Sustainability through Recycling

The primary aim of this review article is to find the influence of wastewater and its characteristics on recycling as an alternative to potable water for concrete preparation. On the other hand, scarcity, and the demand for freshwater for drinking are also increasing day by day around the globe. About a billion tons of freshwater is consumed daily for concrete preparation for various operations such as mixing and curing, to name a few. The rapid development of certain industries such as textile, casting, stone cutting, and concrete production has caused the water supply to be severely affected. Recycling wastewater in concrete offers various potential benefits like resource conservation, environmental protection, cost savings, and enhanced sustainability. This article reviews the effect of various types of wastewater on various physical and chemical properties of wastewater, rheological characteristics, strength, durability, and microstructure properties of concrete. It also explores the potential effects of decomposing agents on enhancing concrete properties. Currently, limited research is available on the use of various types of wastewater in concrete. Hence, there is a need to develop various methods and procedures to ensure that the utilization of wastewater and treated wastewater is carried out in the production of concrete in a sustainable manner. Although wastewater can reduce the workability of fresh concrete, it can also increase its strength and long-term performance of concrete. The use of various types of wastewater, such as reclaimed water and tertiary-treated wastewater, was found to be superior compared to those using industrial- or secondary-treated wastewater. Researchers around the globe agree that wastewater can cause various detrimental effects on the mechanical and physical properties of concrete, but the reductions were not significant. To overcome limited scientific contributions, this article reviews all the available methods of using various types of wastewater to make concrete economically and environmentally friendly. This research also addresses possible challenges with respect to the demand for freshwater and the water crisis.

Study on Bonding Behavior between High Toughness Resin Concrete with Steel Wire Mesh and Concrete

This paper investigates the interfacial bonding behavior between high toughness resin concrete with steel wire mesh (HTRCS) and concrete. A total of five sets of fifteen double shear specimens were tested for parameters including concrete strength and material properties of HTRCS composites. The test results showed that the failure mode of DS1 specimens was partial debonding and fracture, and the rest of the specimens were the fracture of HTRCS. The concrete strength and reinforcement ratios of HTRCS composites were positively correlated with interfacial adhesion properties. When the concrete strength was increased from C30 to C40 and C50, the ultimate load increased by 43.4% and 43.2%, respectively. The ultimate load capacity increased by 32.1%, with the reinforcement ratio of HTRCS composites increasing from 1.05% to 1.83%. Moreover, the bonding slip model and the bearing capacity formula for the interface between HTRCS composites and concrete were proposed, and the calculation values were in good agreement with the test values, with an average value of 0.978.

Modelling and analysis of strength and durability properties of internal curing concrete using PEG 400 and artificial neural network

The traditional curing processes necessitate a large amount of water. This is especially difficult in locations where there is a lack of water and for construction of high-rise structures. In this research article, we provide a remedy by inventing concrete that will not require additional water for curing. In the present work, polyethylene glycol was utilized as an internal curing agent in varying percentages. The internally cured concrete with polyethylene glycol was cured at ambient conditions, whereas the conventional concrete without polyethylene glycol was kept in water for curing. Fresh and hardened characteristics of concrete with and without polyethylene glycol are compared. The results revealed that 1.5% polyethylene glycol is an optimum percentage where maximum strength and durable properties are achieved. The microstructure of internal curing concrete indicates that the pore sizes are small compared to conventional concrete. The crystallite size is smaller in internal curing compared to conventional concrete mixtures, resulting in an acceleration of the hydration process in concrete with smaller crystallites.Further experimental results are compared with ANN. Predicted results are very close to experimental values.

Sustainable reuse of waste ceramic tiles powder and waste brick powder as a replacement for cement on green high strength concrete properties

Nowadays, reducing construction waste has grabbed the attention. As bricks and ceramic tiles represent more than 50% of the ceramic waste in many European countries. Thus, the recycling of this waste type is one of the most significant challenges within the paradigm of the circular economy. This paper investigated the impact of substitution levels of cement by waste ceramic powder (WCP) and waste brick powder (WBP) at 0%, 5%, 10% and 15%, on the HSC characteristics. The WBP and WCP materials were characterized in detail by laser granulometry, XRF and XRD measurements, followed by standard mixing, production, and curing of concrete samples. The experiments on dry density, modulus of elasticity, flexural strength, splitting tensile strength, compressive strength, resistance to sulfate attack, water absorption and ultrasonic pulse velocity were conducted to evaluate the hardened properties of concrete. It was demonstrated that the durability and strength of concrete containing WBP and WCP as partial replacements for cement are marginally inferior to those of the control sample. On the other hand, samples containing WBP had a lesser negative effect on HSC properties in comparison with samples containing WCP. However, employing a 5% WBP with 10% WCP mixture enhanced the characteristics of the HSC in comparison to samples containing various percentages of WCP individually. In addition, the microstructure analyses revealed that the addition of 10% WCP and 5%WBP to HSC specimens resulted in higher hydration products and a slightly denser concrete matrix compared to samples containing various percentages of WCP individually. Research findings indicate that a 15% substitution of cement with WCP or WBP illustrated an environmental benefit in concrete production due to a 13.1% reduction in specific energy consumption.

Investigating Concrete Properties with Partial Replacement of Cement by Alccofine and Eggshell Powder

In this study, we investigate the effect of substituting cement with Alccofine and eggshell powder on the strength properties of concrete. Cement production is a significant source of carbon dioxide emissions, prompting the search for sustainable alternatives. Our research aims to address this environmental concern by evaluating the potential of Alccofine and eggshell powder as partial cement replacements while maintaining or enhancing concrete quality. We prepared various concrete mixtures with a constant 10% substitution of Alccofine, combined with different proportions of eggshell powder replacing cement (ranging from 0% to 20%). Through thorough testing including compressive, split tensile and flexural strength assessments, we analyzed the mechanical performance of these mixtures. Our findings demonstrate that Alccofine and eggshell powder can effectively substitute cement in concrete, providing a more environmentally friendly option that improves material strength. However, further research is needed to optimize the mix proportions and assess long-term durability in diverse environmental conditions. Notably, combining eggshell powder with Alccofine presents a promising approach to enhancing concrete performance while reducing the environmental impact of cement production. This study contributes to advancing sustainable practices in concrete construction, promoting the use of eco-friendly building materials. Key Words: Alccofine, eggshell powder, compressive, split tensile and flexural strength.

Enhancement fracture behavior of sustainable cementitious composites using synergy between fly ash (FA) and nanosilica (NS) in the assessment based on digital image processing procedure

The present study has investigated the strength properties and fracture toughness of concrete composites reinforced 5 % nanosilica (NS) by adding different contents of fly ash (FA), i.e.: 0 %, 15 % and 25 %. The evaluated fracture toughness, under three-point flexural loads, were critical stress intensity factor (KIcS) and critical crack tip opening displacement (CTODc). Digital image processing procedure was used in this studies. It was stated that both the 5 % addition of NS and the total share of the nanomodifier with FA grains in the composition of the concrete mix significantly improve the strength properties of concretes, as well as their fracture toughness under first model of cracking in linear and non-linear terms. Moreover, it was observed that in concrete containing only NS the fracture process was clearly delayed and relatively short, whereas crack patterns in this composite were almost perfectly straight with significant crack width. On the other hand, in concretes icorporating NS + FA crack patterns were strongly curved (frequently with branching) with few microcracks in the vicinity of the main cracks. Concretes including FA and NS can be used in the execution of specific types of reinforced concrete structures subjected to fatigue or dynamic loads, e.g. bridge structures or industrial buildings.

The enhancement of engineering characteristics in recycled aggregates concrete combined effect of fly ash, silica fume and PP fiber

In today's world, enhancing the performance of recycled aggregate concrete is an essential need, as it ensures the effective utilization of demolished construction waste. The advantages of fly ash and polypropylene fiber in conventional strength concrete are well known. However Further research is required to evaluate the impact of using fly ash, silica fume and polypropylene fiber in case of RA and its effect on the properties of recycled aggregate concrete (RAC). This study evaluates the effects of using 50%, 75%, and 100% recycled aggregate (RA) and 1%, 2%, and 3% polypropylene fiber with a fixed amount of fly ash and silica fume 87 kg/m3 and 21.75 kg/m3. The objective is to determine how these combinations affect concrete strength and durability properties (compression, tensile strength, acid resistance and water absorption). This study also investigates the reliability of non-destructive tests, ultrasonic pulse velocity and rebound number, in the presence of polypropylene (PP) fibers and fly ash with recycled aggregate. The experimental investigation showed that the combination of RA based concrete, fly ash (FA), and polypropylene fiber (PPF) improved concrete durability and strength. The concrete compressive strength made with 50% RA was 13% lesser than that of control concrete, but with the incorporation 3% PP fiber the same mix achieved 5% higher strength than control mix. On the other hand, the concrete compressive strength made with 75% RA and 100% RA was experimentally found 19% and 22% lower, respectively than control mix. The combinations containing constant fly ash and PPF, in addition to 50% recycled concrete aggregate (RCA), demonstrate greater resistance when exposed to sulfuric acid (H2SO4) environments, in comparison to the control mixture. However, the worst performance is shown by mix (100% RA).

Health assessment of TBM diversion tunnel structure based on AHP and AMV models

Health assessment is one of the important theoretical bases for deciding whether the diversion tunnel can operate safely and stably. A project of the TBM diversion tunnel is taken as the research object to ensure the normal operation of the diversion tunnel. Based on measured data and considering multiple safety aspects such as structural response, durability, and external factors of the diversion tunnel, a TBM diversion tunnel structural health evaluation index system is established. A new method for the TBM diversion tunnel structural health comprehensive evaluation based on Analytic Hierarchy Process-Matter Element Extension-Variable Weight Theory (AMV) is proposed to explore the impact of AMV fluctuation with the measured results of the indicators on the weight, closeness, and health grade of each evaluation index. The high sensitivity and high-risk evaluation indicators for the structural health of the diversion tunnels are identified. It is found that the variable weight varies with the changes in various indicator values, which can accurately evaluate the health status of tunnels in real-time. The characteristic values of the tunnel grade calculated by the AHP and the AMV are 1.589 and 1.695, respectively. The results of the corresponding interval diversion tunnel are the basic safety state of grade B. Except for the two evaluation indicators of concrete strength and slurry properties, the variable weight values and grade characteristic values of other evaluation indicators increase with the increase of indicator values. The four indicators of segment settlement, segment opening, segment misalignment, and segment cracks are more sensitive to the health of the TBM diversion tunnel. This AMV can accurately evaluate the health status of the diversion tunnel structure. The research results can provide references for later maintenance work and similar projects.

Assessing Novel Fiber Reinforcement Against Conventional Mix by Using Both Natural and Synthetic Fibers in Concrete with Statistical Performance Analysis

This research investigates the effect of incorporating innovative human hair fibers (HHF) and polypropylene fibers (PPF) into concrete, which has been observed to enhance the material’s strength characteristics. These fibers augment the concrete’s tensile strength and resilience, fortifying it against cracks and elevating its overall endurance. This research delves into the impact of reinforcing concrete specimens with human hair and polypropylene fibers. These specimens are employed in cube, cylinder and flexural beam tests. Both fresh and hardened properties, such as compaction factor and slump, and compressive, split-tensile, and flexural strength at varying curing periods (28 days and 90 days) and the ratios (1%, 2%, and 3%) are considered by weight of cement. Specifically, the 3% polypropylene fiber concrete mix exhibited the highest average compressive strength at both 28 and 90 days, while the 2% polypropylene fiber mix showed the highest split-tensile strength. Flexural strength results followed a similar trend. Results show that 3% HHF addition leads to notable improvements in concrete strength properties, albeit not as significant as with polypropylene fibers. Statistical analysis, including independent samples Kruskal–Wallis tests, was conducted to compare the distributions of strength values across different groups. The statistical analysis indicates significant differences in strength distributions across groups, with p-values below the significance level of 0.05. This underscores HHF’s potential as a sustainable alternative in construction applications, contributing to enhanced concrete strength.

Modeling of Strength Properties of Porous Concrete

According to previous research, porous concrete has lesser compressive strength than normal concrete and can only withstand mild traffic loads. The demand for high-strength porous concrete is urgent. By balancing the elements of porous concrete, high strength porous concrete may be produced. This may be accomplished by comprehending the complicated interaction between porous concrete's constituents. Using artificial intelligence approaches, the present research offers a study on the prediction of 7, 28-day compressive strengths and 28, 90- day flexural strengths of porous concrete. Random tree (RT), M5 Rules, REP Tree, and ensemble with Bagging were used to estimate the compressive strength of porous concrete in this work, and a comparison of performance and practicality of artificial intelligence result is shown. A total of 111 datasets were extracted from prior research and publications. As input parameters for modelling, cement, natural coarse aggregates, recycled coarse aggregates, water, silica fume, plastic/steel/rubber fibres, and density were employed. Properties such as mean absolute error, root mean square error, and correlation coefficient were used to evaluate and compare the behavior of projected models. The results demonstrated a high level of capacity and potential for predicting the compressive of porous concrete.

Experimental investigation of Bamboo Leaf Ash and Rice Husk Ash as partial replacement cement in concrete

Construction work was mostly done in the ancient era using mudstone obtained from industry. The experimental investigation on the strength properties of M30 grade concrete, in which rice husk ash and bamboo leaf ash have largely substituted cement. One of these waste materials produced as a by-product of the rice paddy milling industry is rice husk ash (RHA). and Bamboo is used as scaffolding for the manufacture of domestic goods and construction paper. In this investigation, concrete specimens created with 0%, 5%, 10%, and 15% of the RHAsh and BLAsh as the cement replacement percentages were used to calculate the strength-related parameters such as compressive strength, splitting tensile strength, and flexural strength. Samples were examined at 7, 14, and 28 days old. Finally, it was determined that, when compared to other replacement levels, the 5% RHAsh and BLAsh replacement level in M30 grade concrete demonstrated to be greater.

DEVELOPMENT OF COMPRESSIVE STRENGTH PREDICTIVE MODELS OF SELF-COMPACTING CONCRETE CURED USING DIFFERENT CURING METHODS

Curing is the process of controlling the rate and extent of moisture loss, relative humidity and temperature from newly poured concrete for a certain period of time after it has been cast or finished to ensure that the cement has been properly hydrated and the concrete has hardened. The concrete strength, durability and other physical properties are affected by curing and application of the various types as it relates to the prevailing weather conditions in a particular locality, as curing is one of many requirements for concrete production, as such it is important to study the effect of different curing method. The concrete cube specimens produced with cement, fine aggregate, and coarse aggregate mix-ratio of 1:2.23:1.62 were prepared with a water-cement ratio of 0.5 and superplasticizer (SP) dosages of 0.5%, 1.0%, and 1.5%. The SP dosages were computed as percentages by weight of the cement content. The cubes were tested for compressive strength after curing for 7, 14, 21, 28, and 56 days using three curing methods namely; Immersion, open air, and wet burlap curing methods. This study assessed the effect of different curing methods on compressive strength of self-compacting concrete through the development of a mathematical method to model and analyze the effect of the curing methods used on the compressive strength of the SCC and also to validate the reliability of the method used. Data Fit software was used in the model development, the curing age and super-plasticizer dosage were used as independent variables while the compressive strength...

Effect of Non-Class Fly Ash on Strength Properties of Concrete

Developing of green construction and reducing CO2emissions in the environment is a priority for industry in the coming years. Recycling fly ash in the concrete industry is a well-known way to reduce environmental impact. Aside from this benefit, there are numerous other positive effects of incorporating fly ash into concrete; however, in this research, the objective is to replace cement with a different percentage of non-class fly ash with high CaO, more than 42%. The analyzed variables are non-class fly ash properties, the effect of fly ash presence on the main properties of concrete and examining the optimum of non-class fly ash in ordinary concrete C-25/30 and high-performance concrete C-50/60. All investigations took place in the laboratory by producing 24 different mix designs and more than 1000 specimens to examine: consistency, setting time, shrinkage, and compressive strength in the short and long terms of curing. Recycling industrial waste in new construction, especially fly ash because of its non-uniform properties, still has some obstacles and is not a practical issue, but the future must be environmentally friendly, and this research proves that the objective of producing sustainable ordinary and high-performance concrete was achieved by replacing 40% of cement with non-class high CaO content fly ash. Doi: 10.28991/CEJ-2024-010-03-02 Full Text: PDF

Combined Effect of Banana Fibre and Nano Silica on the Strength Properties of Concrete

Abstract: This study investigates the combined effect of nano silica and banana fibres on mechanical properties of concrete of grade M-25. Nano silica has been used as a partial replacement of cement by weight. Nano silica has been kept constant at 3% as maximum strength was achieved at this percentage according to past studies. Banana fibre has been added by weight of cement in proportions of 0.5%, 1%, 2%, 3%, 4% and 5%. Length of banana fibres kept at 40mm. Compressive strength was determined by using different combinations of nano silica and banana fibre. Nano concrete provides good strength as compared to conventional concrete. The addition of banana fibres in nano concrete improved the strength properties of nano concrete as well as improvement in crack resistance of concrete. On the other hand, the addition of banana fibres resulted in reduction workability as well as permeability of concrete

Optimization of waste tyre steel fiber and rubber added foam concretes using Taguchi method and artificial neural networks

This research presents a study on the waste tyre steel (WTS) and rubber particles (RP) added foam concrete using Taguchi method and Artificial neural networks (ANN) by revealing its potential utilization in construction industry. The fresh and hardened characteristics of foam concretes were experimentally tested. Twenty-five different samples were first prepared according to the Taguchi design and compressive and flexural strengths, dry density and thermal conductivity of the samples were optimized. A Quasi-Newton based ANN algorithm was proposed to obtain prediction equations for the flexural and compressive strength of foam concretes. ANOVA analysis was also conducted to determine the most important factors. The results showed that the combined utilization of WTS and RP decreases the harmful effect of RP on the strength properties of foam concretes. Taguchi optimization results were confirmed through validation tests. With the proposed ANN method, R2 values were obtained as 0.9775 for compressive strength, 0.9723 for flexural strength, 0.9654 for dry density and 0.9527 for the thermal conductivity measurements. Both Taguchi and ANN system were found to be suitable for the design and estimation of the responses.

Effects of Waste Plastic and Glass Aggregates on the Strength Properties of Ambient-Cured One-Part Metakaolin-Based Geopolymer Concrete

The production of Portland cement (PC) is associated with carbon emissions. One-part geopolymer “just add water” is a user- and environmentally-friendly binder that can potentially substitute PC. However, there is limited research on the setting time, fresh, and strength properties of one-part metakaolin (MK)-based geopolymer concrete (OMGPC) incorporating recycled aggregates. Hence, the study explored the fresh, mechanical (compressive, flexural, splitting tensile, and E-modulus) and microstructural properties of ambient cured (7-, 28-, and 90-day) OMGPC containing recycled waste plastics (RESIN8) and recycled fine waste glass aggregate (FWG) at 5% and 10% by volume of the sand. The study result shows that 2% trisodium phosphate by wt. of the binder retard the initial and final setting times of OMGPC. At the same time, the incorporation of RESIN8 and FWG aggregates improved the workability of geopolymer concrete. The lightweight properties of RESIN8 aggregate reduce the hardened density of OMGPC, while the FWG specimens show a similar density to the control. The compressive strength of RESIN8 and FWG OMGPC range from 19.8 to 24.6 MPa and 26.9 to 30 MPa, respectively, compared to the control (26 to 28.9 MPa) at all curing ages. The flexural and splitting tensile strength of the OMGPC range from 2.2 to 4.5 MPa and 1.7 to 2.8 MPa, respectively. OMGPC is a viable alternative to Portland cement, and FWG can substitute sand in structural concrete by up to 10% and RESIN8 aggregate at 5% by volume of the natural sand.

Effect of Aluminium Fiber on the Strength property of Concrete

This experimental work is aimed at determining the influence of aluminium waste fiber on plain cement concrete. To achieve this aim, compressive strength test has been conducted. The compressive strength test has been conducted in Compression machine. The plain cement concrete with the ratio 1:1.5:3 at 0.55 water cement ratio has been utilized in this study. Aluminium waste has been used as additional material in concrete. The weight of aluminium has been taken from 0.5%, 1.5% and 1.5% by weight of cement of varying aspect ratios that are 2.5 (length=0.5 inch, width=5mm), 5 (length=1inch, width=5mm) and 7.5 (1.5 inch, 0.5mm). A total number of ten batches, each batch contained six cubes and were casted for evaluation of compressive strength test. The curing ages selected for this particular study have been 7 and 28 days. It has been observed in this study that aluminium waste has resulted into a decrease in compressive strength of concrete as compared to normal concrete. This study has made application of solid waste as addition material in concrete. Therefore, this study will be helpful to reduce environmental pollution.

EFFECT OF DOSE AND TYPES OF THE WATER REDUCING ADMIXTURES AND SUPERPLASTICIZERS ON CONCRETE STRENGTH AND DURABILITY BEHAVIOUR: A REVIEW

As one of the concrete admixtures, water reducing admixtures and superplasticizers are usually used to reduce the mixing water volume and improve the performance of the harden concrete while maintaining better workability of the fresh concrete. However, the concrete strength and durability properties are affected differently by different types and dosages of the water reducing admixtures and superplasticizers. Based on the published literatures, this paper comprehensively reviews and analyzes this problem. Different types of the concretes, including ordinary Portland cement concrete, ordinary Portland cement concrete containing pozzolan, fly ash and ground granulated blast furnace slag, calcium sulfoaluminate cement concrete, ferrite aluminate cement concrete, recycled aggregates concrete, lightweight aggregate concrete, self-compacting concrete and ultra-high performance concrete, are considered to discuss the influence of types and dosages of the water reducing admixtures and superplasticizers on their strengths. Water absorption, frost resistance and permeability resistance of the concrete are mainly reviewed to discuss this influence on the durability properties of the concrete. Then, some suggestions on the application of the water reducing admixtures and superplasticizers in reinforced concrete structures and projects are proposed.

Valorisation of the Effect of Waste Aluminum Sawdust on Concrete: Durability Characteristics and Environmental Impacts

The aim of this study is to examine the effect of replacing waste aluminum sawdust (AS) with fine aggregate on the strength and durability properties of concrete. For this, concrete mixtures with a cement dosage of 400 kg/m3, water/cement (W/C) ratio of 0.40-0.50-0.60 were prepared. Aluminum sawdust obtained from Elazığ industrial site was added to the concrete mixtures by replacing 0%, 0.5% and 1% fine aggregate by volume. After curing in the curing pool for 28 days, the produced concrete samples were placed in the carbonation tank and exposed to the accelerated carbonation test in three different time periods as the 1st, 3rd and 7th days. Tests of compressive strength, splitting tensile strength, ultrasound transmission velocity, porosity and carbonation depth were performed on concrete samples before and after carbonation. The samples that were exposed to carbonation were compared with the samples that did not undergo carbonation. In addition, the microstructure of AS concrete was investigated using scanning electron microscopic images (SEM). In the microscopic images, larger cracks, openings and interfacial voids were observed in the concrete matrix with the addition of AS. However, due to the formation of ettringite in these gaps and cracks after carbonation, the cavities became smaller. As a result of the experiments, it was observed that the optimum W/C ratio was 40% and the AS amount was 0.5% in the use of AS in concrete. In addition, it was found that the carbonation effect improves the compressive and splitting tensile strength and increases the ultrasound transmission rate. Finally, life cycle assessment (LCA) was conducted to evaluate the environmental impacts of the prepared concrete samples. Considering the large amount of natural aggregate consumption, it is thought that the use of waste materials in concrete will provide environmental and economic benefits.

Utilization of Agricultural By-Products as a Partial Replacement of Cement in Construction: A Review

Food and Shelter are the two main requirements for surviving in this cosmos. More than 50% of the geographical area of the country is under cultivation. After harvesting the rice crop there is a common practice to set fields on fire. This stubble burning creates havoc causing a large number of health hazards and also affects the soil properties. This method of decomposition of agricultural residue including rice straw and rice husk if replaced with some standard combustion conditions, temperature, and rapid cooling of ash produced, will prove beneficial to the construction industry. This review paper explores the possibility of utilizing these agricultural waste products i.e. Rice Straw Ash (RSA) and Rice Husk Ash (RHA) as a partial replacement of cement in concrete and analyzing the fresh and hardened properties of concrete. Research gaps and future scope of this study are also highlighted in this review paper. It has been observed that the physical, chemical, and strength properties of concrete are mostly affected by the pozzolan city of the ashes and compressive strength and tensile strength of concrete increases with increase in replacement level of cement with the agricultural ash up-to certain optimal levels. Various other factors that contribute to the enrichment of the existing properties of the resulting concrete include grinding, fineness and porosity of ashes.