The use of a high amount of calcined clays as cement replacement presents a great challenge in designing self-consolidating concrete. This current attempt evaluates the influence of cement replacement with up to 40 vol.% by a calcined common clay (CC), dominated by 2:1 phyllosilicates in combination with a fixed limestone powder (LP) content on fresh and hardened properties of self-consolidating mortar (SC-M). The fresh properties of SC-M were investigated by mini-slump flow, V-funnel and rotational viscometer measurements. Setting and hardening behavior were observed via dynamic modulus of elasticity and plastic shrinkage. Hydration mechanisms were determined by isothermal calorimetry and thermal analysis. Hardened properties of SC-M were evaluated using compressive strength tests and mercury intrusion porosimetry (MIP). The results revealed a decreased rate of deformability in SC-M when cement is substituted increasingly by CC and a rising superplasticizer (SP) demand, but indicated an improved stability of SC-M even at a higher dosage of SP and hardly any impact on the setting behavior. CC enhanced the precipitation of monocarboaluminate phases and thereby refined the pore size distribution of the binder matrix. SC-M can be produced with up to 40 vol.% CC as cement replacement without having effect on its 28 days mechanical properties.

As the construction industry grows, it produces large volumes of construction waste, which has a tremendous environmental impact and generates public concern in the neighbouring towns. The construction industry generates a significant volume of waste and faces a challenge with poor construction waste minimisation in order to prevent adverse environmental and dumping impacts worldwide. In developing countries, regional waste management systems have increased problems. Environmental pollution (air, water, and soil) and human health issues are caused by waste produced in a country as a result of different cultural, social, and religious activities. Prior studies were reviewed to choose dimensions and items for the data gathering instrument. A pilot test was conducted to identify potential questionnaire adjustments, and hypotheses were tested using structural equation modelling (SEM). A total of 220 Malaysian construction professionals answered the survey, which yielded the results. Five hypotheses have direct correlations based on the findings, three of which have a significant effect. Furthermore, the findings reveal that policy-related factors mediate the relationship between improving factors and sustainable construction waste minimisation. In contrast, they did not mediate the relationship between current practices/generation and sustainable construction waste management. The established framework can help improve construction waste management and help achieve global sustainable development goals. The data reveal that adopting preventive plans to reduce construction waste is one of the most important aspects of enhancing profitability. This study could aid construction industry players in evaluating waste management components during the construction and design stages of a building project.

One principal approach to achieve self-compacting properties is the increased amount of finer constituents of the mixture. This, in turn, increases cement consumption leading to higher greenhouse gas emissions. Pozzolanic materials, like rice husk ash or calcined highly kaolinitic clays, have gained increased attention as supplementary cementitious materials in self-compacting concrete production. These materials could be viable alternative supplementary cementitious materials for sub-Saharan Africa which already lacks fly ash, slag and silica fume. This current effort reviews the impact of rice husk ash and calcined clays for the production of self-compacting concrete. Special focus is on their impact on rheological, mechanical and durability properties of self-compacting concrete. Rice husk ash and, in particular, calcined highly kaolinitic clays are introduced as technical and cost-effective supplementary materials for use in self-compacting. The review disclosed a lack of knowledge when it comes to the use of low-kaolinitic calcined clays as sole SCM or together with rice husk ash, which could be a very promising combination for e.g., several countries in Africa. Further studies are needed on the rheological properties, shrinkage, creep, and durability of self-compacting concrete produced with other calcined common clays and their blend with rice husk ash.

As a result of rapid population growth, an exponentially growing human population, and industrial expansion, it has become increasingly difficult to manage municipal solid wastes throughout the world. Decentralized waste management systems have created difficult situations in developing countries such as Malaysia. Wastes generated in the country, due to various cultural, social, and religious activities, organic and contributing to environmental pollution (air, water, and soil) and human health troubles. A questionnaire survey was participated by 220 construction professionals in Malaysia using structured and semi-structured methods. The framework was assessed using A partial least square structural equation modeling (PLS-SEM) to target sustainable development goals (SDG). Statistical analysis results indicate a significant effect between SCW management, since(r(270)=.687, P<0.001). Improving factors has strong relationship with SCW management, since(r(270)=.723, P<0.001). The mediation results also suggested a significant indirect positive effect of improving factors drivers on SCW management through policy-related factors sinceβ=0.688, t=8.254, P<0.001, 95% CI for β=0.536,0.866. Finally, policy-related factors construct has a strong relationship with SCWM) management, since(r(270)=.811, P<0.001) With the R Square of 0.787 and 0.785. The developed framework can improve construction waste management in the construction industry and enhance construction waste management to achieve global sustainable development goals. The findings show that one of the most critical issues of enhancing profitability is using preventive policies to reduce construction waste. This study could guide construction industry stakeholders in identifying the different waste management features during a building project's construction and design stage

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