Use of Recycled Sand Produced at Construction Sites in Bedding Mortars

Abstract

The aim of this paper is to present a proposal for the recycling of construction and demolition waste (CDW) at construction sites and the use of recycled sand in bedding mortar. Three samples of CDW were collected at construction sites from the city of Recife, Brazil and milled in a hammer mill. The following properties of the recycled sands were analyzed: water absorption, material finer than 75 μm, bulk density, fineness modulus, and the presence of contaminants. Mortars were produced with different amounts of cement and replaced the natural material by recycled aggregate in proportions of 50, 75 and 100%. These mortars were characterized for compressive strength, fresh mortar density, and consistence. Masonry prisms with three ceramic blocks were produced for analyzing the bending and shear strength. Several correlations between the properties of aggregates, mortar, and prisms were obtained, leading the authors to propose a recycling process, dosage, and quality control methodology for bedding mortars prepared with recycled sand at construction sites.