The HPFRC refers to a category of fiber-reinforced cement-based materials that have the remarkable capability to flex and strengthen prior to shattering. At present, research is being conducted with the intention of producing a worldwide guideline for the development of structures using HPFRC. However, due to its high initial price and constrained availability, its implementation is challenging, particularly in developing countries. In this study, the effects of fly ash (FA) and rice husk ash (RHA) were examined, with 10%, 20%, and 30% of the cement replaced with FA. Furthermore, the mix providing maximum compressive strength was then taken to replace the silica fume content at 10, 20, 30, and 40% by RHA, steel fiber was also added to optimize the compressive and flexural ductility performance of the specimens. An extensive evaluation of fresh, mechanical, microstructural, and durability of HPFRCs were carried out. In addition, the eco-mechanical properties of fiber-reinforced concrete are studied by taking into account the post-peak behavior of the manufactured specimens and associated CO2 emissions. Test results show that the maximum improvement in compressive, tensile, and flexural strengths was 6.49%, 12.85%, and 5.27%, respectively, at 10% RHA replacement. In addition, as the concentration of RHA increased, the flexural bending toughness increased between 7.4% and 9.2%, with good agreement between the analytical models and the experimental results of the uniaxial compressive stress–strain. Moreover, the gradual increase in RHA concentration improved the durability of the HPFRCs, as evidenced by a maximum reduction in sorptivity coefficient of up to 48 percent for 30% RHA replacement. Finally, the investigation shows how the eco-mechanical index (EMI) can be used to evaluate material design options for HPFRCs. 

To ensure the safety and long-term integrity of concrete infrastructures, cracks in concrete composites, whether self-started or induced by external loads, are nearly inevitable and often difficult to detect and fix. As a result, Self-healing concrete composites, which can automatically restore small cracks, are essential for the long-term development of infrastructure. Several aspects of autogenous and autonomous healing concretes are discussed in this study, including their manufacture, characterization, processes, and performances. Mineral admixtures, fibers, and curing agents, as well as autonomous healing methods such as shape memory alloys, capsules, and microbial technologies, have been shown to be effective in partially or completely repairing minor fractures. As a result, some of the mechanical qualities and durability of concrete infrastructure can be recovered. It has been found that autonomous approaches heal cracks better than most autogenous methods, which can only repair fissures with a width of less than 150 μm. Shape memory alloys, capsules, or bacteria-based self-healing concrete are all examples of biomimetic materials that are being researched in the field of material science. As a result, self-healing technology can be used to develop smart materials and intelligent structures, allowing concrete structures to adapt and respond to changes in their surroundings. 

The HPFRCs are recognized by a special combination of cementitious composites with high durability, high strength, and deformability. However, due to the high initial price and constrained availability of materials like Silica Fume, its implementation is challenging, particularly in developing countries. In this study, the effects of fly ash (FA) and rice husk ash (RHA) were examined, with 10%, 20%, and 30% of the cement replaced with FA. Furthermore, the mix providing maximum compressive strength was then taken to replace the silica fume content at 10, 20, 30 and 40% by RHA, steel fiber was also added to optimize the compressive and flexural ductility performance of the specimens. An extensive evaluation of durability, mechanical, microstructural characteristics of produced HPFRCs were carried out. In addition, to evaluate the sustainability of produced mixes, a lifecycle evaluation was carried out utilizing the recipe midpoint and endpoint technique. Test results show that the uniaxial compressive resistance was significantly enhanced at RHA concentrations up to 20%. Moreover, the gradual increment of RHA concentration enhanced the durability performance of HPFRCs, as evidenced by a reduction in the sorptivity coefficient of up to 30%. In addition, the LCA assessment revealed significant reduction of crucial environmental factors, such as CO2 emissions, fine particle discharge, ozone depletion, and land use with the gradual integration of RHA and FA.

This research goal is to evaluate the characteristics of glass powder (GP), quartz powder (QP), and limestone powder (LP) as Supplementary Cementitious Materials (SCMs) to replace cement content in terms of fresh and hardened properties of Self-Compacting Concrete (SCC) for sustainable building construction. Moreover, the obtained results were modelled using a soft computing approach. This investigation created ten mixtures incorporating varying percentages of GP, QP, and LP by replacing cement at about 0 %, 10 %, 20 %, and 30 %, respectively. The slump flow and J-ring tests were done to observe how SCMs affected the properties in fresh conditions. In addition, the mechanical properties and pore structure configuration of the specimens were investigated. It was observed that GP and LP positively affected the fresh properties, increasing the mixes flowability by up to 8 %. Moreover, 20 % GP was able to enhance the compressive strength by 7 % by improving the pore structure of the cement matrix, which was confirmed by the mercury intrusion porosimetry analysis. Finally, the built machine learning models indicated good accord with test outcomes for Artificial Neural Network (R2 = 0.95) and could be applied to calculate the compressive strength of concrete containing GP, QP and LP for the construction housing sector. 

High-Performance Self-Compacting Concrete (HPSCC) has attracted much attention in recent decades due to its remarkable ability to fill formworks with densely packed reinforcing bars while requiring minimal or no external compaction. Because of the negative environmental impacts of cement and natural aggregates in concrete production, a much more sustainable alternative to manufacturing HPSCC is required. Recycled glass waste is one of the most attractive waste materials that can be used to create sustainable concrete compounds, which is currently a major area of study among researchers. This study aims to develop information not only about the fresh, mechanical, and durability characteristics of HPSCC, evaluate the environmental impact and correlate the crushing strength using a non-destructive approach by utilizing waste glass aggregates at replacement percentages of 0%, 10%, 20%, 30%, and 40%. To improve the performance of the produced HPSCC, Metakaolin was also added. The results of the fresh concrete tests revealed that the substitution of an optimal level of waste glass with Metakaolin provides adequate implementation in flowability, passing ability, and viscosity behaviors. Even though there is a reduction in the mechanical performance with glass aggregates, Metakaolin significantly improved strength and ductility by up to 16.12% and 15.91%, respectively. Furthermore, in most cases, the use of glass aggregates with Metakaolin significantly alters the durability properties of concrete while minimizing the environmental impact as well as the overall project cost. Finally, the NDT assessment demonstrates that the analytical equation can efficiently predict the compressive strength and promising to use for field application. 

The requirements of higher cement content and numerous admixtures in self-compacting concrete (SCC) yield a comparatively high production due to the high cement consumption that limits its use in everyday construction. As a result, it is prudent to consider alternatives for decreasing the environmental effects while producing a cost-effective SCC. Therefore, this study aims to investigate the fresh mechanical, durability, and microstructural characteristics as well as the environmental impacts of self-compacting concrete (SCC) incorporating waste banana leaf ash (BLA) to determine the optimum percentage of BLA. Concrete mixtures with 10%, 20%, and 30% OPC substitutions were investigated. Test findings revealed that all the fresh mixes performed within the EFNARC (2002) recommended limit. Despite the fact that increasing concentrations of BLA reduced the mechanical properties, concentrations of up to 20% BLA demonstrated strength comparable to the control mix. Furthermore, chloride ion penetration increased to 4%, with 20% BLA replacement falling into the moderate ion permeability zone. Finally, a relatively lower CO2-eq (maximum 29.13% reduction) per MPa indicates a significant positive impact due to the reduced Global Warming Potential (GWP). 

Self-consolidating concrete (SCC) has many advantages compared to traditional concrete. However, it often suffers from high brittleness that limits its various applications. Reinforcing the SCC by fiber inclusion can be a fruitful way to enhance its performance. This study aims to investigate how the rheological and mechanical characteristics of SCC are affected by the addition of jute fibers for a specific length of 20 mm at various volumetric fractions of 0.1%, 0.25%, 0.50%, 0.75%, and 1%. Slump flow, J-ring flow, V-funnel, L-box, and Sieve stability tests were performed to investigate the rheological properties of jute fiber reinforced self-consolidating concrete (JFR-SCC); while, compressive, splitting tensile, and flexural strength tests were conducted to determine mechanical properties at 7 and 28 days. Scanning electron microscopy (SEM) testing was also used to examine the microstructures of JFR-SCC. These rheological and hardened states were then compared with the control SCC. JFR-SCC performed satisfactorily in terms of flowability, viscosity, and segregation resistance. However, adding more than 0.25% jute fiber in SCC mixes significantly affected the passing ability. The maximum improvements in compressive, splitting tensile, and flexural strength were 2%, 21%, and 18%, respectively, over the reference mix at 28 days. The jute fibers can fill the microcracks in concrete and prolong the ultimate failure. Hence, SCC with jute fiber can be adopted as an eco-friendly alternative to SCC with artificial fibers. 

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.

Purpose – This study aims to present the variations of optimal seismic control of reinforced cement concrete (RCC) structure using different structural systems. Different third-dimensional mathematical models are used to examine the responses of multistory flexibly connected frames subjected to earthquake excitations.

Design/methodology – This paper examined a G+50 multi-storied high-rise structure, which is analyzed using different combinations of moment resistant frames, shear walls, seismic outrigger systems and seismic dampers to observe the effectiveness during ground motion against soft soil conditions. The damping coefficients of added dampers, providing both upper and lower levels are taken into consideration. A finite element modeling and analysis is generated. Then the nature of the structure exposed to ground motion is captured with response spectrum analysis, using BNBC-2020 for four different seismic zones in Bangladesh.

Findings – The response of the structure is investigated according to the amplitude of the displacements, drifts, base shear, stiffness and torsion. The numerical results indicate that adding dampers at the base level can be the most effective against seismic control. However, placing an outrigger bracing system at the middle and top end with shear wall can be the most effective for controlling displacements and drifts.

Originality/value – The response of high-rise structures to seismic forces in Bangladesh’s soft soil conditions is examined at various levels in this study. This study is an original research which contributes to the knowledge to build earthquake resisting high-rises in Bangladesh.

So many mediums to high-rise buildings have suffered major damage from past major earthquakes in Nepal, China, Turkey, India, and other countries, including people's lives and safety. Because Bangladesh has not experienced a major earthquake in the last several centuries, a tremendous amount of energy has been stored and is ready to be released at any time. The current practice of seismic design is limited to demand estimation and analysis and thus cannot guarantee that the design structure meets the initial objectives. As a result, a performance-based approach should be initiated. Khulna is located in Bangladesh's seismic zone I, which indicates that the city has a moderate likelihood of experiencing earthquakes. While the likelihood of catastrophic vulnerability is low, urban areas are more vulnerable than rural areas due to their higher population density. This study emphasizes the importance of performing performance-based seismic design for RC buildings and investigates the seismic performance of an educational building located at the Khulna University of Engineering and Technology (KUET). The building was designed as per BNBC-2006, but the latest issued BNBC-2020 demands a complete new seismic evaluation complying latest code. Non-linear pushover analysis is carried out using ETABS v-16 software. The VBA program models plastic hinge properties of beams and columns using stress-strain models for concrete and steel according to BNBC-2020. The building's design base shear is compared to the requirement earthquake base shear. The global response of the structure is also examined for estimating the safety of the building under demand earthquake loading in terms of capacity curve, hinge placement, and ductility ratio.

Under working load conditions, foundation settlement is a critical design consideration. Well-designed foundations cause stress-strain states in the soil that are neither linear elastic nor perfectly plastic. Often, rather than bearing capacity, settlement dictates the construction of footings on sandy soil as well as soft clay condition. Settlement forecasts are therefore vital to the development of shallow foundations. The effect of surrounding footings is often neglected while assessing the geotechnical capacity of isolated footing considering permissible settlement criteria. In this study, the impact of a variable distanced surrounding footing is assessed under soft soil conditions. A finite element analysis is performed using geotechnical finite element analysis software PLAXIS. A substantial capacity variation is observed with varying numbers of footings and distances. Thus the consideration of this capacity variation can predict more safer design.

The compressive strength of Ultra-High Performance Concrete (UHPC) is a function of the type, property and quantities of its material constituents. Empirically capturing this relationship often requires the utilization of intelligent algorithms, such as the Artificial Neural Network (ANN), to derive a predictive model that fits into an experimental dataset. However, its black-box nature prevents researchers from mathematically describing its contents. This paper attempts to address this ambiguity by employing two deep machine learning techniques – Sequential Feature Selection (SFS) and Neural Interpretation Diagram (NID) – to identify the critical material constituents that affect the ANN. 110 UHPC compressive strength tests varying based on the material quantities were compiled into a database to train the ANN. As a result, four material constituents were selected; mainly, cement, fly ash, silica fume and water. These material constituents were then employed into the ANN to compute more accurate predictions (r2 = 80.1% and NMSE = 0.012) than the model with all eight material constituents (r2 = 21.5% and NMSE = 0.035). Finally, a nonlinear regression model based on the four selected material constituents was developed and a parametric study was conducted. It was concluded that the utilization of ANN with SFS and NID drastically improved the accuracy of the model, and provided valuable insights on the ANN compressive strength predictions for different UHPC mixes.

As the production of toxic gases increases due to the consumption of natural resources, the concrete sector has to emphasize more on sustainable sources such as palm oil fuel ash (POFA). In this study, the influence of varying concentrations of POFA on the rheological and mechanical performance of structural concrete is investigated. Cement content was partially replaced by POFA at 5%, 15%, 25%, 35%, and 45% respectively. To analyze the fresh qualities, rheological tests including slump, density, and compacting factor were conducted. The mechanical performances including compressive strength, flexural strength, and splitting tensile strength were also evaluated. POFA provided to an overall improvement in the workability of the rheological tests, as the increase in slump varies from 9 to 46%. In addition, significant enhancement in compressive, splitting tensile and flexural strength was also observed due to incorporation of POFA. Attained results were compared with different standards and the impact of POFA on the environment was evaluated by performing eCO2 emission. The optimal results of mechanical performance were attained incorporating 5% to 15% of POFA and significant improvement was evaluated in terms of sustainability and cost-effectiveness.

This study investigated the effects of aluminium dross (AD) with optimum and high percentage of fly ash (FA) as partial cement replacement in cement-based materials. AD was used in amount of 10% and FA in 25% and 60% to study the physical and mechanical strength properties of modified cement-concrete at 7, 14, 28, 56 and 84 days. The same amount of replacement was used to study the microstructure behaviour of modified cement-paste at selected 28 and 84 days based on the optimum results. The test results revealed that replacement of cement by AD alone in cement-concrete cannot improve the volume of permeable void (VPV) and water absorption (sorptivity), even reduce the concrete strength.  However, combination of optimum percentage 25% FA with 10% AD in cement shows lower rate in water absorption (sorptivity) test as compared to control for both 28 and 84 days and gave the denser and smoother look in SEM surface morphology image at 28 days. The pozzolanic reaction and pore-filling effect of proposed pozzolan and filler into cement-based materials hydration process can be seen through the correlation of microstructure and physical properties of cement-based material, where the Boron Nitride (BN) was predicted to contribute into pore-filling effect activity of cement-based materials based on the findings. Hence, the effect of combination of AD and FA in cement-based materials as partial cement replacement was believed can be use in non-structural application.

In this article finite element model (FEM) is prepared for RC beam which is flexurally strengthened with carbon fiber reinforced polymer (CFRP) laminate. The 3D analysis is conducted using ABAQUS software and the results are investigated, where ultimate load carrying capacity, mid-span deflection and strain characteristics of both reinforcement and concrete are analysed numerically. Later these parameters are investigated experimentally in a similar way by keeping all the important conditions such as loading, reinforcement detailing, boundary condition etc. identical. This comparative assessment illustrates that, the using of CFRP has a significant advantage to improve flexure behaviour of RC beams. Various types of failure mode such as deflection and stress for whole cross section and for only reinforcement are achieved from FEM analysis. In addition, typical deflection, stress and strain contours of a specified node are found for unstrengthen and CFRP strengthened beam. This article also approves the possibility to predict the strain characteristics of both reinforcement and concrete for strengthened and unstrengthen RC beams and found a precise similarity while comparing with FEM results. Furthermore, in terms of ultimate load, the deviation in result is as narrow as 4% for flexurally strengthened RC beam by CFRP laminate.

Self-compacting concrete (SCC) is extensively used in the construction industry due to its high flowability and no requirement of mechanical vibration. While, the enormous amount of waste tire produced each year in the world engenders significant environmental impacts. These tire rubber can potentially be used in the construction market as value-added concrete aggregates. The objective of this study is to investigate the fresh and hardened properties of SCC with varying waste rubber tire aggregates as a partial replacement of coarse aggregates. In this study, conventional coarse aggregates were replaced by waste rubber tire aggregates (WRTA) with a proportion of 0%, 5%, 10% and 20% to find out the optimum percentage of coarse aggregates replacement with rubber. This produced a light weight concrete as rubber acts as a contributing factor for reduction of dead load due to its light weight. The consequences on fresh properties were investigated by the slump flow, J-ring and V-funnel test while compressive and splitting tensile strengths tests were conducted to assess hardened properties. Observed test results indicated a reduction in workability and hardened properties with the increment of WRTA. In contrast, 5% replacement of coarse aggregates with rubber showed the best results however 10% replacement with rubber aggregates is feasible to generate self-compacting rubberized concrete (SCRC), implementing a sustainable approach to reduce environmental impacts and managing a vast amount of rubber tire waste in an efficient environment friendly way.