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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.

Indeed due to global advancement, rapid technological innovation, and enhancing regional influence, supply chain (SC) has become an essential element. Now, competition has shifted from organization to industry level; any disruption can not only disturb organization but also effect whole industry. Although Malaysia is known from palm oil and rubber but manufacturing sector has highest growth rate (7.1%) and second contributor to GDP and employer. Due to regional and economic shift toward China and India this sector is facing numerous problems. Supply chain collaboration has dogged the performance in various industries and in various regions. The aim of this study is to explore the potential benefits of supply chain collaboration toward achieving operational performance. This is an empirical investigation conducting among manufacturing industries in Malaysia. Factor analysis and multiple regressions through SPSS have been used for data analysis. The finding of this study reveals that two supply chain management approaches information sharing (IS), joint decision making (JDM) significantly effect, while Electronic Data Interchange (EDI) does not have a significant effect on operational performance.

Concrete is highly utilized construction material around the globe and responsible for high depreciation of the raw materials. Consumption of this material in construction industry is arching upward day by day. On the other hand, debris of demolished concrete structures are being dumped as waste. For developing countries such waste is not a good sign and need its proper utilization by recycling it into useful product. In this consequence, this study is an attempt to utilize demolished waste concrete by converting into coarse aggregates. This research was conducted on recycled cement concrete aggregates of demolished structures and Rice Husk Ash (RHA). The purpose of this experimental study is to analyze the mechanical properties of concrete; when cement is partially replaced with RHA and natural aggregates by recycled aggregates (RA). In this study, the cement was replaced by RHA up to 10% by weight of cement. For experimental purpose, total 135 concrete specimens were prepared, cured and tested in Universal Testing Machine (UTM). Finally, laboratory results were compared in terms of compressive and splitting tensile strength made with normal and recycled coarse aggregates. All the specimens were prepared at 1:1.5:3 with 0.50 w/c ratio and tested at 7, 14, 21, 28 and 56 days curing ages. It is observed from experimental analysis that the workability of fresh normal concrete is 7% and 10% greater than recycled aggregates concrete blended with 10% RHA and only recycled aggregates concrete without RHA respectively. The compressive strength increases up to 6%, whilst splitting tensile strength increases 4% at 56 days curing, when the cement is replaced 10% by RHA. It is, further, concluded that with more than 10% RHA replacement with cement, the compressive strength decreases. This study would help the construction experts to use such wasted concrete into useable production of new concrete projects.

Concrete, which is made of cement, fine and coarse aggregates and water, is the most used building material in the world. It's durable, strength and ease of availability have been its main advantages. Concrete is strong in compression while it is known to be weak in tensile. Over the years different methods and materials have been utilized to reinforce concrete to overcome such weakness. Fibre reinforcement has shown considerable improvement in the properties of concrete. Therefore, in this study, M20 grade concrete was reinforced with steel fibres which were added at a volume fraction of 1%, 2%, 3%, 4% and 5% and compared with a control sample with no steel fibres. The effect on the workability of concrete with the steel fibre reinforcement was determined as well as the effect on flexural and compressive strengths concrete. Based on the results, the reinforcement of steel fibres had a significant adverse impact on the workability, with the increase in fibre content, the workability decreased. On the other hand, a significant enhancement was observed in the mechanical properties of concrete with the addition of steel fibres, achieving higher strength than the control sample. The highest compressive and flexural strength was gained with the addition of 3%, a further increase in fibre content decreased the strength. Therefore, the optimum dosage of steel fibres was determined to be 3%. Although the compressive and flexural strengths are still higher at 5% reinforcement compared to controlled sample.

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Concrete which is widely used material in the construction industry, has a carbon footprint. Approximately 10% of global Carbon Dioxide (CO2) gas is emitted during the production of cement which is vital ingredient of concrete. The increase in production of cement affects global warming and climate change. Therefore, many have attempts have been made to develop green and sustainable concrete by utilizing different waste materials. With the utilization of waste materials as cement replacement, the CO2 gas emissions can be reduced as well as resolve the environmental issues that the inhabitants face during the disposal of such waste materials. This paper reviews the potential and innovative utilization of Rice Husk Ash (RHA) and Eggshells as partial cement replacement to develop green concrete. RHA which is rich in silica and eggshells contain identical amount of calcium oxide as cement, when finely grinded and used together as partial cement replacement, can trigger a pozzolanic reaction, in which silica reacts with calcium oxide resulting in the formation of calcium silicates which are responsible for achieving higher strengths.