The application of waste marble as coarse aggregate in concrete production / Kok Yung Chang, Wai Hoe Kwan and Hui Bun Kua

The massive growth of construction industry especially in the developing countries results in extensive quarrying activities which ultimately would lead to the depletion of natural resources. Apart from extensive extraction of the natural granite from the earth for concrete production, marble production industry is also majorly contributing to the quarrying activities. In addition, high volume of waste is generated by the marble production industry as 70% of marble is wasted during the production such as quarrying, cutting, processing and others which is environmental unfriendly. In a way to achieve sustainable construction, the present study is to utilise the waste marble in replacing the coarse aggregate in concrete production. The engineering performance including workability, compressive strength, ultrasonic pulse velocity (UPV) and chloride penetration were analysed. The raw waste marble obtained from the industry were crushed and sieved into maximum size 20 mm and used to replace the coarse aggregate at the level of 20%, 40%, 60%, 80% and 100% respectively. Results show that 60% of the replacement level has yield to optimum result by achieving the highest compressive strength and UPV at approximate 5% higher than the control. Meanwhile, the effect on chloride penetration resistance is more significant, i.e. approximate 19% better than the control. However, increasing the replacement level of waste marble has no significant effect on workability, although an increasing trend was observed

Toward Sustainable Construction: Use of recycled aggregate in concrete in Malaysia

This paper reviews several key issues related to the use of natural aggregate (NA) for concrete production, in view of the high demand for materials to meet the rapid construction development in Malaysia. The current paper aims to discuss the potential of recycling waste concrete to generate recycled aggregates (RA) that may be used as alternative aggregate sources in the production of concrete. Moreover, several major challenges to the use of RA for concrete production are also highlighted. This paper also provides an action plan to encourage the construction industry’s wide usage of RA to achieve sustainable construction.  Keywords: construction; recycled aggregate; sustainable; waste concreteeISSN 2398-4279 © 2018. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open-access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.

Optimisation on the Hybridisation Ratio of Pulverised Fuel Ash and Ground Granulated Blast Furnace Slag (PFA - GGBS) for the Fabrication of Geopolymer Mortar

The current cement industry has several environmental and social problems, including high greenhouse gas emissions, air pollution, water consumption, and the generation of large quantities of waste. This matter has grown into a significant concern, and there is now a pressing requirement to substitute the conventional binding material in concrete, namely Ordinary Portland Cement (OPC). This paper presents the report on the hybridisation of two industrial by-products, namely pulverised fuel ash (PFA) and ground granulated blast furnace slag (GGBS), to produce an alternative binder known as geopolymer. A set of 11 hybrid PFA-GGBS geopolymeric mortar mixes was created using the complete range of hybridisation ratios, along with different water-to-binder ratios. The freshly mixed hybrid PFA-GGBS geopolymeric mortar was put through a flow table test to examine the required water-to-binder ratio to achieve the targeted level of workability. Afterward, all the samples were allowed to cure at room temperature before undergoing a destructive test to measure their compressive strength. According to the study's findings, the highest compressive strength of 4.6 MPa was achieved with a PFA-GGBS hybridisation ratio of 60-40 in the geopolymeric mortar. However, when the content of GGBS exceeded 40 %, the compressive strength of the hybrid PFA-GGBS geopolymeric mortar produced tended to decrease. Additionally, as the replacement level of GGBS increased, the required water-to-binder ratio also increased to maintain the targeted level of workability, ranging between 0.31-0.41. The PFA-GGBS hybridisation ratios of 60/40, 50/50, 40/60, and 30/70 have shown promising properties to be further refined regarding their application in cementless concrete. Moreover, the study conducted to replace cement as a binder in concrete has the potential to make the construction industry more sustainable and reduce carbon emissions by utilising industrial waste ash that would need to be affordable, strong, durable, and widely available in order to be practical