Experimental analysis of eco-friendly mortar with industrial waste

Abstract

The use of industrial waste in cementitious materials is a major challenge for the construction industry. In many sectors, the waste usually presents heterogeneity in terms of volume and production composition, which hinders its use on a large scale. However, cementitious materials such as laying and covering mortars, as well as concrete, if properly proportioned, can tolerate a certain amount of waste. To ensure a systematic and accurate analysis of the system formed by waste plus cementitious composites, it is necessary to use semi-empirical methods that combine experimental results with mathematical models. The present study presents an analysis of mortars with polyurethane (PU) industrial waste and foundry exhaust sand (FES). This analysis is presented in different scenarios. First, a bibliometric survey was created to map the main authors, journals and keywords used. Second a study of the mechanical, physical behavior and workability of conventional mortars with partial replacement of natural sand with polyurethane waste, in this model a Design of Experiments (DOE) was used to plan and analyze the responses. Third, a delimitation of the range of percentages used for the control variables of the second experiment was performed, these variables were percentage of sand by cement (S/C), coarse sand content (SC), percentage of substitution of FES by natural sand (FES), percentage of substitution of PU by natural sand (PU). In this way it was possible to perform a response surface (RSM) through a quadratic model by means of the developed DOE. The fourth scenario of the study involved the dynamic analysis of mortars with waste in which it was possible to obtain the dynamic behavior of the mortar structure. Numerical models were created for all the situations tested, these models proved capable of providing data to adjust the predictive indices that influence the mechanical, physical and dynamic quality of the mortars tested. The results serve as a basis for the development of more sophisticated and optimized methods for dosing and incorporation of waste in cementitious composites on a large scale