Due to over exploitation of natural sand for the building industry, the use of substitute for fine aggregates such as silica sand is a natural step in resolving the partial reduction of natural aggregates. Research into the diversity of concrete structures dates back to the first half of the century. Concrete made by using silica sand as fine aggregate has been studied to determine the compression and Flexural strength. Therefore, in this research, silica sand was used to replace conventional fine aggregate with a different percentage for making M20 concrete with a water cement ratio of 0.40. Percentage replacements are 25%, 50%, 100% by natural fine aggregates. Cubes and beams are casted and tested for compressive and flexural strength. According to the obtained experimental results, it is proven that silica sand is one of the best ways to integrate nature and can be used in concrete to obtain high compression strength and flexibility.

The environment friendly and creative material in the construction field is the Geopolymer concrete. The two main constituents of Geopolymer are the source material and the alkaline liquids. In previous studies, alternate for alumino silicate source material as wood ash in geopolymer concrete was found and optimized with fly ash. Moreover, from the previous literatures it could be noted that, GPC had a less brittleness and energy absorbent. To improve the brittleness and energy absorption capacity polypropylene fibre and rubber fibre were added by 0, 0.25, 0.5, 0.75, and 1 % of volume fraction at different ratios. Further, effects on addition of polypropylene and rubber fibres of the optimized wood ash-fly ash based low calcium geopolymer were studied. In the previous study, hybridization of fibres was found out. On other hand, concrete paver block has major disadvantages of less skid resistance, less strength, less energy absorbent, less slip resistance. Hence, the research on finding an alternative to the cement paver block is needed. Ferro-cement was a wonderful technology in the construction industry which have tendency to give more strength to the structure. In this study, the low calcium ferro-geopolymer paver block for an alternate of cement paver block was proposed. Meanwhile, the ferrogeopolymer technology was used by varying the different type of meshes and different layout patterns of meshes. The optimized ferro-geopolymer paver block is going to be produced by varying the shape and size of paver block, surface texture of the paver block. The compressive behaviour, split tensile behaviour, and flexural behaviour is going to be studied for the optimization of low calcium ferro-geopolymer paver block. Micro-structural characterization is also going to be studied for the detailed understanding of inside reaction of low calcium ferro-geopolymer paver block by SEM and EDX.

This paper investigates the effects of pozzolanic substitutions for ordinary Portland cement (OPC) with silica fume (SF) and metakaolin (MK) on the mechanical and toughness performances of steel fiber reinforced concrete (SFRC). Initially, a reference concrete mix with a water-to-binder ratio of 0.4 is blended with different volume fractions of steel fibers with varying geometry: crimped steel (CS) and straight steel (SS), both individually and in combination, to examine their mechanical properties. In the subsequent phase, the study investigates the impact of combining macro- and microsteel fibers on flexural toughness, to determine potential synergy for suitable combinations. Also, the possible influence of pozzolans in the variation of flexural toughness of hybrid steel fiber reinforced concrete (Hy-SFRC) was evaluated. Hybridization of steel fibers was found effective in improving the workability of the concrete mix up to 11%. SFRC mixes containing pozzolans exhibited a significant enhancement in compressive strength, modulus of rupture, and modulus of elasticity compared to non-pozzolanic SFRC. The hybrid combination of CS 1.5% and SS 0.5% was considered the best in terms of mechanical properties. Additionally, the results of synergy assessment showed that hybridization of steel fibers in the pozzolanic concrete mix was particularly effective in the post-cracking stages with a positive 14% compared to a negative 8% in the pre-cracking stage. The pozzolanic addition improved the flexural toughness of Hy-SFRC to about 10%-20%. Blending of SF and MK in Hy-SFRC was found effective in enhancing the toughness mechanism of concrete compared to Hy-SFRC mixes containing binary SF and MK, indicating a stronger bond between the fibers and the matrix resulting from the pore refinement and hydration products developed at the interface. Hy-SFRC containing a ternary pozzolanic mix of SF 10% and MK 10% gave the best results in flexural toughness, and the corresponding synergy values were found to be the maximum. The results were consistent with the morphology analysis, which revealed an increase in hydration products at the interface between the aggregate and concrete matrix, as well as between the steel fiber and concrete matrix, due to the ternary blending of SF and MK.

The need for concrete is growing rapidly every day and cement is utilized to satisfy the requirement for development of infrastructure. The manufacturing of cement products generates a massive concentration of carbon dioxide (CO2) that impacts the ecosystem and surroundings, creates pollution as well as hazardous to human beings. In an effort to minimize the demand for cement and CO2 emission, in this study, alternating cementitious ingredients such as Ground granulated blast furnace slag (GGBFS) and silica fume (SF) were utilized. In this study, NaOH and Na2SiO3 were used to generate ground granulated blast furnace slag based geopolymer concretes that contained various proportions of silica fume, which were then cured at room temperature. Rheological, hardened, and durability properties were investigated. NaOH (14M) and Na2SiO3 were utilized as alkaline solutions to activate the geopolymerization. The findings indicate that the incorporation of SF increased the compressive, splitting tensile and flexural strength of geopolymer concrete. The geopolymer concrete has been observed highly reliable in the existence of 2 percent of sulphuric acid, 5 percent of sodium sulphate and 5 percent of sodium chloride.

The CO2 emissions from cement have had significant negative consequences on the environment, necessitating the substitution of cement in the production of concrete. This research tends to cover the mechanical characteristics and microstructural studies of concrete formed by replacing some of the cement with Alccofine (AL) by percentages of 5%, 10%, 15%, 20%, 25% and 30% and some of fine aggregate with Glass Powder (GP) by percentages of 10%, 20%, 30%, 40% and 50% in the concrete of the M40 grade. A pozzolanic substance called alccofine and high silica content material called glass powder was extensively utilized in the building industry. When the mechanical properties of concrete were tested at various time periods, the optimal partial cement and fine aggregate substitution was determined to be 20% Alccofine and 50% of Glass Powder. When compared to conventional concrete of the same ratio, the compressive strength of the concrete has been enhanced at 20 percent replacement of AL and 50 percent replacement of GP. Moreover, concrete was subjected to a microstructural examination to observe the hydration process at various time intervals, and the results clearly demonstrated how pores and C-S-H (calcium-silicate hydrate) gel are created in both early ages and later ages. According to the study's findings, cement may be replaced in part without impairing its properties and can help lessen the impact of CO2 on the environment.

Concrete is typical utilized material that requires a lot of cement and energy to produce and emit carbon dioxide (CO2), need to find an alternative. Self-Compacting Geopolymer Concrete (SCGC) is a sustainable engineering method in industrial ecosystems which do not need shaking and cement. In this study, the effects of fly ash (FA) andGround Granulated Blast Furnace Slag (GGBS) based SCGCwith sodium silicate and sodium hydroxide solutions as activatorson fresh and mechanical properties was investigated. The constant binder concentration of 0.45 and binder weight of 450 kg/m3 are used. GGBS replacement with FA was 0 %, 25 %, 50 %, 75 %, and 100 % weight percentage in each SCGC. The fresh properties were investigated by using tests such as slump flow, T50cm, V-funnel, and L-box. The mechanical properties of SCGC were evaluated by compressive, split tensile, and flexural tests at 7 and 28 days. The GGBS and FA dosage is optimized, and results show that 50 % treatment of the GGBS and FA has enhanced hardening qualities in SCGC 3 mix. Superplasticizers (2 %) was used to maintain fluidity of the SCGC. This study shows the designed SCGC is cost-effective building material for precast and cast in situ constructions under ambient conditions.

The demand for cementless concrete in the construction sector is increasing by every day due to the global warming scenario of the world. In this study, industrial waste named GGBS along with Metakaolin has been utilized as the binders for the production of geopolymer concrete at varying proportions ranging from 0 to 100

Green building materials are being developed around the world to limit the demand for rapidly depleting environmental assets, including greenhouse gas emissions. Geopolymers are significant in this environment, and various studies have considered a range of substances as suitable binder materials. In this dissertation, the workability and mechanical properties of geopolymer concrete mixes made using industrial by-products such as fly ash (FA) and Ground Granulated Blast Furnace Slag (GGBS) was determined by varying the FA and GGBS proportions (0–100

Most development projects are experiencing claims having numerous causes. Since 2010, claim disclosures have increased as a result of the overall political climate. These allegations had a significant impact on every group involved in the building industry. The consequences of the claim could include expense invasion, loss of efforts and job interruption, and contract termination. This examination intends to perceive the simple explanation behind the guarantees in development and exhibit their contrast between respondents regarding the specific, organizational, and association attributes. It also points out the significant variables in producing for the administration of development project claim to anticipate a guaranteed event and alleviate a case's negative effect. The target of the examination was accomplished through a questionnaire survey from a few development organizations. The poll study was led, including the project worker, specialist, customer perspective. The consequence of the study experienced in the SPSS programming for finding the primary consideration that influences the development. The finding shows the nonattendance of site consideration regarding recognizing cases, separation or difficulty to reach of related archives proactively, and clashes created during proprietor/worker for hire exchange are essentially fundamental problems associated with the arrangement of construction claim management system. Through survey paper, this work hopes to identify various claims and identify the factors that have the greatest impact on construction claims in our southern region.

Cement production is the major source of global warming which induces 7% of total greenhouse gas emissions. Reducing the use of cement in construction industry needs to be adopted by any of the alternates. One of the best alternates to reduce the impact caused by the cement production process is geopolymer concrete which can completely replace the usage of cement. Geopolymer is trending technology which possess numerous advantages than ordinary Portland cement concrete technology. Geopolymer is produced by the mixing of solid precursor and monomer. Most widely used solid precursors are waste industrial byproducts such as fly ash, GGBS, metakaolin etc., and monomers are alkaline activators like sodium hydroxide and Na2SiO3. Meanwhile, the properties of geopolymer concrete are decided by the various parameters such as quantity of aluminosilicate source in precursor, ratio of NaO/SiO2, SiO2/Al2O3, NaOH/NaSiO3, solution to binder ratio, concentration of NaOH etc., The alkaline activators mostly used are chemical activators which is harmful to humans. Hence, there is a need of finding an alternate for chemical activators in the geopolymer concrete. In this proposed methodology, the chemical alkaline activators have been completely replaced by the waste residue product named coffee husk. Coffee husk is a residue produced from the coffee powder production industry. A total of 18.29 MMT of coffee husk ash has been produced every year. Coffee husk has an inbuilt composition of potassium which is one of the alkaline activators. However, the coffee husk ash needs to be calcinated by the use of oven before to use. In this research, an attempt has been made to utilize the Coffee husk ash (CA), as an alkaline activator and efficient activation mechanism of CA will be examined.

Brittleness poses a significant threat to the durability of cement-based materials over time. The simultaneous addition of pozzolans and fibers offers a novel and eco-friendly approach to tackle concerns regarding brittleness and environmental impacts associated with conventional cement concrete. This paper investigates the effects of pozzolanic substitutions such as silica fume (SF) and metakaolin (MK) for Ordinary portland cement on the mechanical and toughness performances of steel fiber reinforced concrete (SFRC). In the first part of the study, reference plain concrete mix with a water-to-binder ratio of 0.4 is mixed with different percentages of steel fibers with varying geometry, such as crimped steel (CS) and straight steel (SS) fibers, both as individual and hybrid combinations, to determine the mechanical properties. In the second part, the study evaluated how combining CS and SS fibers influence flexural toughness, aiming to identify combinations that may synergistically enhance performance. The study also examined the influence of pozzolans on the flexural toughness of hybrid steel fiber reinforced concrete (Hy-SFRC). An increase in workability was observed due to the hybridization of steel fibers. The increase in compressive strength, modulus of rupture, and modulus of elasticity was greater in pozzolanic SFRC compared to non-pozzolanic SFRC. The ternary mix of SF and MK showed 18.5

As cement is the primary cause of CO2 emission, an attempt is made to replace the cement and it is done by replacing the cement with GGBS and silica fume along with activators such as sodium silicate and sodium hydroxide. By enrolling such materials in concrete, it will ensure the reduction of environmental consequences. This research is done by replacing of the cement with GGBS and silica fume without involving any type of admixtures. And it is done for M 30 grade with varying GGBS i.e., 90%, 80%, 70% and 60%. And to accelerate the pozzolanic effect, silica fume is added in diverse proportions i.e., 10%, 20%, 30% and 40%. Sodium hydroxide is kept constant throughout. Specimens were prepared for testing and ambient curing of 7 & 28 days has done. Tests such as compressive, split-tensile and flexural strength test are performed to obtain the mechanical behaviour of the concrete.

This paper investigates the effects of silica fume (SF) and metakaolin (MK) as cement substitutes on the mechanical properties, shrinkage, and toughness performances of steel fiber reinforced concrete (SFRC). Initially, a reference concrete mix with a water-to-binder ratio of 0.4 is blended with different volume fractions of steel fibers with varying geometries (crimped steel and straight steel), both individually and in combination, to examine their mechanical properties. Also, the possible influence of pozzolans on the variation of drying shrinkage and flexural toughness of hybrid steel fiber reinforced concrete (Hy-SFRC) was evaluated. An increase in workability was observed as a result of hybridization of steel fibers. Pozzolanic steel fiber reinforced concrete (SFRC) exhibited a more significant enhancement in compressive strength and flexural strength compared to non-pozzolanic SFRC. The hybrid combination of CS 1.5% and SS 0.5% was found to be the best in terms of mechanical properties. The addition of SF and MK reduced the shrinkage strain by up to 50% compared to the reference mix. The flexural toughness values for both binary and ternary pozzolanic Hy-SFRC were notably higher than those for non-pozzolanic Hy-SFRC, indicating a stronger bond between the fibers and the matrix. Hy-SFRC containing a ternary pozzolanic mix of SF 10% and MK 10% gave the best results in flexural toughness. The results were consistent with morphology analysis, which revealed an increase in hydration products at the interface between the aggregate and concrete matrix, as well as between the steel fiber and concrete matrix, due to the ternary blending of SF and MK.

In this study, Geopolymer concrete (GPC) blended with fly ash (FA), ground granulated blast furnace slag (GGBS), rice husk ash (RHA), and nano-silica (NS) developed and investigated in three aspects: In the first aspect of GPC (FA+GGBS), FA varied from 0-100% of GGBS at 10 % intervals to determine the optimum proportion of FA-GGBS. In the second aspect of GPC (FA+GGBS+RHA), RHA varied from 0-25% of FA at 5% intervals with a constant of 30% GGBS attained from the first aspect of the study. In the third aspect of GPC (FA+GGBS+RHA+NS), NS was replaced with 1, 3, and 5% with the optimum proportions of GGBS (30%) and RHA (15%) obtained from the first and second aspects of the study. The fresh and hardened properties of GPC were obtained at 7 and 28 days under ambient curing. The compressive strength improved while FA was replaced by GGBS (0-100%) from 27.75 to 45 MPa. Meanwhile, workability has decreased to 0.81 from 0.97. Hence, the optimized proportion of FA and GGBS was obtained as 70:30 from the workability aspect. RHA replacement provided compressive strength increment up to 15% (39.5 MPa), but workability gradually decreased (0.92 to 0.84) from 0 to 25%. So, the optimum proportion of RHA was achieved by 15% from the second aspect. In the third aspect, the workability increased from 0.89 to 0.92 while NS replacement (0-3%) with FA. Also, compressive strength has improved from 39.52 to 41.95 MPa. Thus, the optimized NS proportion gained at 3% of NS. Overall, this study provides a view of industrial by-product utilization as part of GPC in optimal proportions.

Geopolymer concrete (GPC) had less energy absorption, ductility, impact energy, brittleness and to improve the mentioned properties, fibres with different properties and having the potential to enhance the performance of GPC can be incorporated. This study aimed to produce green geopolymer concrete incorporated with fly ash, waste wood ash, waste tire rubber fibre, and polypropylene fibre. In this study, polypropylene and rubber fibre were added by 0-2% (at 0.5% intervals) of volume fractions, and the effects of fibre hybridisation on the mechanical behaviour have been analysed. The results explored that the addition of individual fibre up to 1% attained the maximum mechanical characters at all ages of concrete. The findings showed that the mix with 0.5% PP + 0.5% rubber attains the maximum strength, and the characteristics were increased by 13.5%, 11.1%, and 12%. The research provided an intellectual approach to produce eco-friendly green geopolymer concrete incorporated with waste materials.

On reducing greenhouse gas emissions by the cement industry, geopolymer with an amorphous polymer form was the best alternative. Geopolymer concrete (GPC) was weak in impact strength, brittle, ductile, and energy absorption than conventional cement concrete. Various property fibres with the capacity to improve the aforementioned properties of GPC can be added. Polypropylene fibre with low elastic modulus and waste tire rubber fibre with high elastic modulus was used in this research to improve energy absorption and impact strength. Different modulus fibres such as polypropylene and rubber was added by 0%, 0.5%, 1%, 1.5% and 2% of volume fraction. The effects of adding individual fibres on the mechanical property of eco-friendly geopolymer concrete were studied. In addition, the influence of hybrid fibres on the mechanical features of low-calcium geopolymer concrete was assessed. The research results revealed that the hybridization of 0.5% of polypropylene fibre and 0.5% of rubber fibre showed better performance and achieved maximum strength in all mechanical features such as compressive, flexural, and splitting tensile behaviour. Meanwhile, the optimum hybrid fibres increased the mechanical features by 23.9%, 12.0%, and 15.2%, respectively, at the 28 days of curing ages compared to geopolymer concrete without fibres.

The aim of the study was to determine the efficiency of Self-Compacting Concrete (SCC) manufactured with copper slag and to examine the influence of superplasticizer on the qualities of SCC manufactured with copper slag. In this research investigation, the grade of concrete employed was M40. By substituting fly ash for cement, 40% of the cement was eliminated. Copper slag has been substituted for fine aggregate in various quantities ranging from 10% to 50% in the concrete compositions. In total, six concrete mix proportions have been produced, for which the parameters like water absorption and chloride permeability were evaluated. In addition, these mixtures have been exposed to an acidic, sulphate environments and marine environments, with the intention of assessing the weight and strength loss after 7, 28, 60, and 90 days.

Purpose Demand for Geopolymer concrete (GPC) has increased recently because of its many benefits, including being environmentally sustainable, extremely tolerant to high temperature and chemical attacks in more dangerous environments. Like standard concrete, GPC also has low tensile strength and deformation capacity. This paper aims to analyse the utilization of incinerated bio-medical waste ash (IBWA) combined with ground granulated blast furnace slag (GGBS) in reinforced GPC beams and columns. Medical waste was produced in the health-care industry, specifically in hospitals and diagnostic laboratories. GGBS is a form of industrial waste generated by steel factories. The best option to address global warming is to reduce the consumption of Portland cement production and promote other types of cement that were not a pollutant to the environment. Therefore, the replacement in ordinary Portland cement construction with GPC is a promising way of reducing carbon dioxide emissions. GPC was produced due to an alkali-activated polymeric reaction between alumina-silicate source materials and unreacted aggregates and other materials. Industrial pollutants such as fly ash and slag were used as raw materials. Design/methodology/approach Laboratory experiments were performed on three different proportions (reinforced cement concrete [RCC], 100% GGBS as an aluminosilicate source material in reinforced geopolymer concrete [GRGPC] and 30% replacement of IBWA as an aluminosilicate source material for GGBS in reinforced geopolymer concrete [IGRGPC]). The cubes and cylinders for these proportions were tested to find their compressive strength and split tensile strength. In addition, beams (deflection factor, ductility factor, flexural strength, degradation of stiffness and toughness index) and columns (load-carrying ability, stress-strain behaviour and load-deflection behaviours) of reinforced geopolymer concrete (RGPC) were studied. Findings As shown by the results, compared to Reinforced Cement Concrete (RCC) and 100% GGBS based Reinforced Geopolymer Concrete (GRGPC), 30% IBWA and 70% GGBS based Reinforced Geopolymer Concrete (IGRGPC) (30% IBWA–70% GGBS reinforced geo-polymer concrete) cubes, cylinders, beams and columns exhibit high compressive strength, tensile strength, flexural strength, load-carrying ability, ultimate strength, stiffness, ductility and deformation capacity. Originality/value All the results were based on the experiments done in this research. All the result values obtained in this research are higher than the theoretical values.