This experimental research was conducted to study the combined effect of agricultural by-product wastes on the properties of concrete. The coconut shell ash (CSA) was utilized to substitute cement ...content ranging from 0 to 20% by weight of total binder and sugarcane bagasse ash (SCBA) to substitute fine aggregates (FA) ranging from 0 to 40% by weight of total FA. In this regard, a total of 300 concrete specimens (cylinders and cubes) were prepared using 1:1.5:3 mix proportions with a 0.52 water-binder ratio. The study investigated the workability, density, permeability, and mechanical properties in terms of compressive and splitting tensile strengths. Additionally, the total embodied carbon for all mix proportions was calculated. It was observed that with an increase in CSA and SCBA contents, the workability, density, and permeability reduced significantly. Due to CSA and SCBA being pozzolanic materials, a gain in compressive and splitting tensile strengths was observed for certain concrete mixes, after which the strength decreased. The increase in embodied carbon of SCBA increased the total embodied carbon of concrete; however, it can be said that C15S40 which consists of 15% CSA and 40% SCBA is the optimum mix that achieved 28.75 MPa and 3.05 MPa compressive and tensile strength, respectively, a reduction of 4% total embodied carbon.
Abstract Revolutionizing construction, the concrete blend seamlessly integrates human hair (HH) fibers and millet husk ash (MHA) as a sustainable alternative. By repurposing human hair for enhanced ...tensile strength and utilizing millet husk ash to replace sand, these materials not only reduce waste but also create a durable, eco-friendly solution. This groundbreaking methodology not only adheres to established structural criteria but also advances the concepts of the circular economy, representing a significant advancement towards environmentally sustainable and resilient building practices. The main purpose of the research is to investigate the fresh and mechanical characteristics of concrete blended with 10–40% MHA as a sand substitute and 0.5–2% HH fibers by applying response surface methodology modeling and optimization. A comprehensive study involved preparing 225 concrete specimens using a mix ratio of 1:1.5:3 with a water-to-cement ratio of 0.52, followed by a 28 day curing period. It was found that a blend of 30% MHA and 1% HH fibers gave the best compressive and splitting tensile strengths at 28 days, which were 33.88 MPa and 3.47 MPa, respectively. Additionally, the incorporation of increased proportions of MHA and HH fibers led to reductions in both the dry density and workability of the concrete. In addition, utilizing analysis of variance (ANOVA), response prediction models were created and verified with a significance level of 95%. The models' R 2 values ranged from 72 to 99%. The study validated multi-objective optimization, showing 1% HH fiber and 30% MHA in concrete enhances strength, reduces waste, and promotes environmental sustainability, making it recommended for construction.
Concrete has been extensively used in the development of urban infrastructure works. However, it has the tendency to absorb solar radiations, and these radiations are released back into the air in ...the form of heat energy. Dense concentration of infrastructures releases more heat, causing urban heat island (UHI) effect in which the ambient temperature of the urban areas rises slightly than the surrounding areas. Tropical countries which have a hot climate throughout the year are more affected by the UHI effect. Therefore, thermal insulating materials need to be introduced in the field of concrete construction. Foamed concrete, which has air voids in its matrix, is a potential thermal insulating material. But due to reduced density, it, however, achieves lower strength. Polypropylene (PP) fibres are used to reinforce the foamed concrete and improve its compressive and tensile strengths. In this study, three different densities, 1400, 1600 and 1800 kg/m
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, were cast, and 0.8% PP fibres were added. The thermo-mechanical properties were investigated in terms of thermal conductivity, surface temperature, compressive and tensile strengths with and without the addition of PP fibres. Based on the findings, the addition of PP fibres gained more strength and reduced thermal conductivity in the lower densities of foamed concrete. In contrast, it had an opposite impact on 1800 kg/m
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density. The addition of PP fibres also indicated that it could reduce the surface temperature of higher-density foamed concrete compared to lower densities.
Delays in residential construction projects are common issues in both developing and developed countries. This research aims to identify the key reasons behind these delays in Pakistan. When the ...projects run behind schedule, this can lead to problems such as exceeding the budget, reduced productivity at the construction site, and potentially lower quality work. The study involved a detailed survey using questionnaires that were addressed to industry professionals. Their responses were used to rank the critical factors causing delays. The most significant factors were found to be fluctuating material prices, financial challenges for contractors, underestimating project duration, poor site management, inexperienced contractors, ineffective project management, communication gaps among project stakeholders, shortage of skilled workers, changes in project design, unqualified contractors, and inadequate project planning. Identifying these critical factors through the Relative Importance Index (RII) method can help in addressing and preventing delays in Pakistan's construction projects, ensuring timely completion and better project outcomes in the future.
In the present era, a number of researchers are using either industrial or agricultural priceless products as a basic source of raw materials for the construction industry. These waste products are ...economical and helpful in producing a sustainable environment and reducing environmental pollution, which is called handling waste products. However, this research work was conducted on concrete containing 0.25%, 0.50%, 0.75%, and 1% of jute fiber as reinforcement material and 10%, 20%, 30%, and 40% of wheat straw ash (WSA) as replacement for fine aggregates. Moreover, the separate and combined effect of jute fiber and WSA as a replacement for sand ingredient in concrete is to determine the fresh and hardened properties of concrete. In this research, a number of concrete samples were prepared with 1 : 1.5 : 3 mix proportion at 0.54 water-cement ratio and cured at 28 days. The experimental outcomes displayed that the compressive, splitting tensile, and flexural strengths improved by 32.88 MPa, 3.80 MPa, and 5.30 MPa at 0.50% of jute fiber along with 30% of WSA at 28 days consistently. Similarly, the modulus of elasticity was developed while the dosages of jute fiber and WSA increased together in concrete. Moreover, the permeability and workability of concrete were reduced while utilized jute fiber and WSA increased together in concrete.
The release of carbon dioxide (CO.sub.2) during the production of cement and the increase in waste generation has allowed the construction to focus on sustainability by replacing cement with ...agricultural waste resources such as Palm Oil Fuel Ash (POFA) and Eggshell Powder (ESP). This experimental study focuses on developing sustainable foamed concrete incorporating high content of POFA and ESP as cement replacement with the aim of cement conversion, reduction in natural resources depletion, reduction of CO.sub.2 emissions and cleaner production. Cement was replaced using 30 and 35% POFA and 5 to 15% ESP by weight of cement. It was observed that the flowability decreased with the increase in the content of POFA and ESP; this is due to their ability to absorb water. It was also observed that 40% cement replacement achieved satisfactory compressive strength while the tensile stress loss was significant. This study confirmed that recycling and reusing of POFA and ESP are possible in foamed concrete which could be used for non-structural applications.
Time and cost play an important role in project completion for both developing and developed countries. This study aims to identify the critical factors that influence the time and cost of commercial ...projects in Malaysia. A detailed questionnaire survey was conducted with industry professionals, and the results were analyzed based on the survey responses. The average index method was used to determine critical factors based on responses from professionals. The critical factors that affect time are poor contract management, client fund shortages, late drawing submissions, land acquisition problems, and inadequate surveying before construction. The critical factors identified for cost are delayed client payments, shortage of skilled workers, design changes, errors in the construction process, and changes in top management. This study raises awareness by identifying critical factors to minimize their impact so that construction can be completed on time and according to the defined budget, and maximize the benefits of future projects.
Nowadays, researchers have been on the lookout for eco-sustainable additives such as agro/industrial waste in concrete in order to offset the carbon footprint created by cement manufacturing. ...However, it has been said that the use of agro/industrial-waste-based cementitious materials in concrete improves its quality. However, this study compared the performance of hydrated lime and cement concrete replaced with 5% and 10% Costus englerianus bagasse ash and bagasse fibre for determining the mechanical properties (compressive and flexural strength). Moreover, compressive strength was evaluated on cubical specimens and flexural strength was evaluated on beam samples at 7, 14, and 28 days, respectively. Results showed that the compressive strength and flexural strength of the concretes increased with an increase in the curing age. Also, the compressive and flexural strengths of cement concrete were recorded by 65.38 MPa and 10.86 MPa at 0% bagasse ash or fibre, which performed better than concrete replaced with 5% and 10% bagasse ash and fibre at 28 days, respectively. Besides, the compressive strength of concrete was noted by 53.85 MPa and 48.92 MPa at 10% bagasse ash and 10% bagasse fibre, respectively, while the flexural strength was calculated by 6.86 MPa and 5.54 MPa at 10% bagasse ash and 10% bagasse fibre, respectively, which were higher than that of concrete produced with hydrated lime alone at 28 days. Thus, bagasse ash performed better than bagasse fibre ash as a partial replacement of cement or hydrated lime in concrete production. Therefore, Costus englerianus bagasse ash or bagasse fibre improved the performance of hydrated lime concrete at 5–10% replacement, but higher concrete strength would be obtained in cement replacement than hydrated lime.
The growing demand for cement has created a significant impact on the environment. Cement production requires huge energy consumptions; however, Pakistan is currently facing a severe energy crisis. ...Researchers are therefore engaged with the introduction of agricultural/industrial waste materials with cementitious properties to reduce not only cement production but also energy consumption, as well as helping protect the environment. This research aims to investigate the influence of binary cementitious material (BCM) on fresh and hardened concrete mixes prepared with metakaolin (MK) and ground granulated blast furnace slag (GGBFS) as a partial replacement of cement. The replacement proportions of BCM used were 0%, 5%, 10%, 15%, and 20% by weight of cement. A total of five mixes were prepared with 1 : 1.5 : 3 mix proportion at 0.54 water-cement ratios. A total of 255 concrete specimens were prepared to investigate the compressive, tensile, and flexural strength of concrete after 7, 28, and 56 days, respectively. It was perceived that the workability of concrete mixes decreased with an increasing percentage of MK and GGBFS. Also, the density and permeability of concrete decreased with an increasing quantity of BCM after 28 days. Conversely, the compressive, tensile, and flexural strength of concrete were enhanced by 12.28%, 9.33%, and 9.93%, respectively, at 10% of BCM after 28 days. The carbonation depth reduced with a rise in content of BCM (up to 10%) and then later improved after 28, 90, and 180 days. Moreover, the effect of chloride attack in concrete is reduced with the inclusion of BCM after 28 and 90 days. Similarly, the drying shrinkage of concrete decreased with an increase in the content of BCM after 40 days.
Besides the availability of herbal drugs in accordance with their native areas, mankind appreciates the benefits of green gold for curing the diseases from prehistoric times. The advancement to ...overcome the basic problem of delayed action of these herbal drugs is effectively tackled by the introduction of Nanotechnology specifically in this field. Some of the admiring aspects of this technique are the improvement of the drug delivery system which improves its effectiveness against diseases and worldwide spread of the drug is possible. Deserted land of the Cholistan region, Punjab; Pakistan, provides an excellent source for the supply of many medicinally important plants, attracting researchers for the exploration of Nanomedicines against several diseases. This review emphasizes the importance of Cholistan desert flora and discusses the prospects of the medicinal corridor through the gateway of the Cholistan desert not only in the advanced field of Nanomedicines but also for providing the better living standards.
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