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The purpose of this paper is to develop gather data on the rheological and mechanical properties of self-compacting concrete (SCC) containing varying percentages of waste glass aggregate (WGA). In this current experiment, the coarse aggregate was substituted by adding WGA, with replacement percentages of 0%, 10%, 20%, and 30% by weight being investigated. The rheological properties of SCC were performed to explore the consequence of WGA using various methods, including the J-ring, slump flow, L-box, and V-funnel. In contrast, the compressive, flexural, modulus of elasticity, and stress-strain responses of hardened concrete were assessed in this study. The results of the fresh concrete tests revealed that the substitution of an optimal level of waste glass in SCC provides adequate implementation in flowability, passing ability, and viscosity behaviors. Besides, hardened characteristics were shown to have a steady decrease in strength with increasing WGA content in the concrete mixtures.

PurposeThis paper aims to identify the critical project management success factors and analyze those factors to achieve a sustainable construction industry in Bangladesh.Design/methodology/approachThis study identified 41 major problematic factors from the related literature. In this research, a detailed questionnaire survey was conducted among the experts and stakeholders of the construction industry of Bangladesh. The survey was carried out on a Likert scale and ranked the critical factors using the relative importance index (RII). The 41 problematic factors were divided into five group factors and ranked by the RII index to prioritize the factors. Finally, stakeholders' opinions were analyzed with the critical assessed factors, which was a very effective technique to eliminate the risks and uncertain occurrences in the construction industry of Bangladesh.FindingsThe factors analysis revealed that cost overrun, traffic jam, low wedges, slow payment for completed works and financial issues of the owner were leading critical factors in construction projects. Moreover, the critical factors are divided into five-factor groups, namely, financial management, monitoring and feedback, competency management, communication and coordination management, and risk management, which exhibit 0.767, 0.720, 0.711, 0.710 and 0.658 RII values. After all, the stakeholders' opinion suggested that implementing modern tools and techniques can help to avoid the critical situation in the construction industry of Bangladesh.Practical implicationsThe construction industry of Bangladesh is moving away from stable construction work day by day. Previously, the potential CSFs were discussed unstructured way. Hence, detecting early warning signals in a structured way has become necessary for the building firm's survival.Originality/valueThough some scattered critical issues are discussed in different literature, the critical issues of the Bangladeshi construction industry were not investigated extensively. Therefore, this study finds out the potential critical issues of the construction industry of Bangladesh to accumulate such harmful construction issues in a single platform so that the construction industry can have an overview of them with the help of innovative technologies.

This paper aims to investigate the mechanical performance of high-strength concrete (HSC) made with polypropylene fiber at various high temperatures. In this study, five different concrete compositions having three contents of polypropylene fiber were prepared. Polypropylene fibers were incorporated at 0.5, 1.0 and 1.5 kg/m3 in concrete and the samples were exposed to 25, 150, 350, 550 and 750 °C temperature, respectively. Fresh properties tests, including slump, density, compacting factor and Kelly ball penetration were conducted for fresh concrete. Mechanical properties, such as compressive strength and splitting tensile strength of HSC were investigated for 14 and 28 days at all high temperatures. In addition, scanning electron microscopy analysis was conducted to examine the changes in the microstructure of optimum fiber content HSC mixture. Experimental results exhibited a reduction in fresh properties and improvement in mechanical properties with the incorporation of polypropylene fiber in HSC. High temperature substantially decreased the compressive and tensile strength of all HSC mixtures; however, the inclusion of polypropylene fiber in HSC reduced the relative compressive and tensile strength loss than the control HSC at all high temperatures. The optimum addition of polypropylene fiber content in HSC was found 1.0 kg/m3, which reduced the strength loss at all high temperatures than other fiber contents.

The incorporation of waste materials generated in many industries has been actively advocated for in the construction industry, since they have the capacity to lessen the pollution on dumpsites, mitigate environmental resource consumption, and establish a sustainable environment. This research has been conducted to determine the influence of different rice husk ash (RHA) concentrations on the fresh and mechanical properties of high-strength concrete. RHA was employed to partially replace the cement at 5%, 10%, 15%, and 20% by weight. Fresh properties, such as slump, compacting factor, density, and surface absorption, were determined. In contrast, its mechanical properties, such as compressive strength, splitting tensile strength and flexural strength, were assessed after 7, 28, and 60 days. In addition, the microstructural evaluation, initial surface absorption test, = environmental impact, and cost–benefit analysis were evaluated. The results show that the incorporation of RHA reduces the workability of fresh mixes, while enhancing their compressive, splitting, and flexural strength up to 7.16%, 7.03%, and 3.82%, respectively. Moreover, incorporating 10% of RHA provides the highest compressive strength, splitting tensile, and flexural strength, with an improved initial surface absorption and microstructural evaluation and greater eco-strength efficiencies. Finally, a relatively lower CO2-eq (equivalent to kg CO2) per MPa for RHA concrete indicates the significant positive impact due to the reduced Global Warming Potential (GWP). Thus, the current findings demonstrated that RHA can be used in the concrete industry as a possible revenue source for developing sustainable concretes with high performance.

This study aims to investigate the combined influence of varying concentration of waste steel fibre and fly ash on rheological and mechanical performance of fibre-reinforced concrete (FRC). Cement ...

This paper focuses on the investigation of fresh, mechanical and durability properties of concrete with the influence of fly ash and polypropylene fiber. In this study, cement was partially replaced by 15% and 30% fly ash content in weight; whereas; polypropylene fiber was incorporated in concrete mixes at 0.06%, 0.12% and 0.18% by volume. Twelve concrete mix proportions were developed and slump, density, ball penetration and compacting factor tests were conducted for examining the fresh concrete properties. Besides, mechanical characteristics, including uniaxial compressive and splitting tensile strength of concrete were evaluated at 7, 28 and 90 days. Further tests of concrete durability, including rapid chloride permeability test, sorptivity and water penetration were performed at 90 days. The results exhibited that the incorporation of fly ash developed the fresh concrete properties, while polypropylene fiber decreased the fresh characteristics of concrete. Furthermore, the combination of fly ash and polypropylene fiber in concrete was substantially attained to improve the mechanical and durability characteristics compared to the control mix. Mix proportion of 15% fly ash and 0.12% polypropylene fiber exhibited a pronounced influence on compressive strength, chloride permeability, sorptivity and water penetration compared to other concrete mixtures.

This study aims to investigate the effect of masonry infill wall with opening on reinforced concrete frame due to seismic loading under the influence of storey number and panel aspect ratio. For this purpose, a total of 36 building frames including bare frame and infill frame with door and window opening were analysed by equivalent static analysis (ESA) and response spectrum analysis (RSA) using STAAD.Pro software. The seismic load was applied as lateral loading and then sway, storey-wise deflection, inter-storey drift, bending moment and shear of those frames were evaluated and compared. Results of the parametric study indicated that ESA exhibited higher results compared to RSA for a conventional design of building frames as the bare frame. The bending moment in infill frames with opening concentrated at the top of the ground floor level for RSA whereas it was at the bottom of the ground floor for bare frames. The maximum moment and shear in the infill frames with opening decreased 12%-50% and 2%-47% respectively compared to the bare frame due to the interaction of infill panels with the frame elements.

Hybrid fibre reinforced concrete (HFRC) is one of the most promising construction techniques and repairing material in recent times for the construction industry. Generally, plain concrete has a very low tensile strength and limited resistance to cracking prior to the ultimate load. Fibre hybridization with different types of fibres helps in resisting these cracks in the concrete structures. This research aims to study the rheological and mechanical properties of HFRC made with steel and coconut (coir) fibre in comparison to control concrete. For this purpose, the experimentation was carried out in the laboratory on cylinders and prisms specimens made from conventional (control) concrete and HFRC with 2%, 4%, and 6% of fibre concentration by weight of cement. Besides, the concentration of waste steel fibre was kept at a constant rate of 1% for all of the HFRC mix in this study. The rheological properties of HFRC mixes were obtained by slump test, compacting factor test, ball penetration test, and density test. These properties were then compared to the corresponding properties of control concrete. On the other hand, compressive strength test, splitting tensile test and flexural tests were performed to attain the mechanical properties of HFRC. The test results indicate that the incorporation of hybrid fibres in the concrete decreases the concrete workability compared to the control concrete. The experimental results showed that the compressive strength is improved compared to the control mix whether the splitting and flexural strength shows an 18.36% and 24.87% improvement over the control mix. Finally, the inclusion of optimum content of hybrid fibres that is 2% by weight of cement showed enhancement in the mechanical properties of HFRC in terms of compressive, tensile and flexural strength with compared to control concrete.