Research on manufacturing of precast concrete hollow wall panels using thermoelectric ASH and slag as replacements for natural aggregates

Abstract

Precast concrete hollow wall panels have emerged as a compelling choice in the construction industry because of their lightweight characteristics, which effectively mitigate structural burdens, coupled with their commendable acoustic and thermal insulation properties. Additionally, their expedited construction process provides a significant advantage over labor-intensive brick wall alternatives. It is noteworthy that the production of these precast concrete panels heavily relies on the utilization of natural aggregates, a practice that has raised concerns, particularly in light of the progressively dwindling reserves of sand resources within our country. Concurrently, there is an escalating volume of ash slag emissions from coal-burning thermal power plants in Vietnam. Therefore, research endeavors aimed at exploring alternative materials, specifically the incorporation of thermal power ash and slag wastes into concrete production for the manufacturing of precast hollow wall panels, assume a dual significance—both from a scientific and practical perspective. These initiatives not only alleviate the strain on our natural aggregate resources but also offer a sustainable solution for managing thermal power wastes, thereby carrying substantial environmental and societal implications. This article presents empirical findings derived from a comprehensive investigation into the integration of thermoelectric ash and slag as substitutes for natural aggregates, encompassing replacement ratios ranging from 70% to 100%, within the production processes of precast concrete hollow wall panels, employing extrusion technology. The results unequivocally demonstrate that with a replacement rate of up to 100% of aggregates with thermoelectric ash and slag, the quality of wall panels using thermoelectric ash slag completely meets the technical requirements according to TCVN 11524:2016 "Wall panels hollow precast concrete using extrusion technology" for use in construction projects.