In the effort to produce sustainable concrete, considerable attempt has been placed on replacing the main ingredients in concrete mixtures with more sustainable materials with the objective to reduce the carbon footprint. One of the replacement materials is waste paper sludge ash (WPSA), a local industrial by-product generated abundantly by newsprint mills which possesses considerable cementitious properties. Parallel to this, the high amount of construction waste, particularly concrete waste has become a difficult environmental issue to cope with in todays world. For this reason, recycling of concrete waste as a new alternative aggregate is being effectively utilized in concrete production. Thus, this paper reports on a study conducted to evaluate the compressive strength characteristics of the potential of using WPSA as a binder and fine recycled concrete aggregate (FRCA) as a virgin sand replacement in producing foamed concrete. The findings of this study exhibited that the inclusion of WPSA and FRCA for replacement ratios up to 20% and 15% respectively has significantly influenced the strength properties of foamed concrete.

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The COVID-19 disease has created the largest disruption in human history, affecting all sectors especially educational systems. Closure of schools, universities, and other educational premises due to pandemic has forced higher education and researchers to create a new alternative way on how to alleviate this problem. E-learning and online instructions is one of the most notable methods that is highly recommended during this pandemic. Thus, this paper aims to investigate the experiences and challenges in learning Civil Engineering Materials (CEM) during COVID-19 pandemic among Civil Engineering Studies (CES). This quantitative study data was conducted to 159 students who enrolled in the CEM course. The student's experiences and challenges while undergoing online learning sessions and how the students can adapt to the CEM course with the new learning environment is the main concern of this study. The result showed that most of the students had a variety of problems such as internet access, discomfort, and inappropriate places to complete the required assessment. Whilst facing the risk of loss of enthusiasm in learning, lack of focus and lack of communication skills between the teaching staff and friends.

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A study was conducted to explore the effect of palm oil boiler ash (POBA) on foamed concrete by varying the percentage of POBA over sand quantities (0, 4, 8 and 12%). This paper primarily discusses the water absorption test, uniaxial compressive strength, and dry density findings. It indicates that substituting sand with POBA greatly enhances the strength of foamed concrete. When the quantity of POBA was raised up to 12% throughout all curing times, the compressive strength steadily increased in the range of 4.34–13.50 N·mm–2. Furthermore, the dry density of foamed concrete was shown to be directly related to the fraction of POBA in the mixture. The dry density of foamed concrete increases as the amount of POBA increases. Despite this, water absorption shown that increasing POBA increases water absorption percentage in foamed concrete from 7.4 to 10.4%. This is due to the fact that a composition with a high POBA percentage will generate more pores than a mixture with a low POBA percentage.