Production of lightweight aggregate from clay

Abstract

The present study covers the production of lightweight aggregates using clay was investigated. The main aim of this research is to produce lightweight aggregates. Clay is the main raw material used in this study because the raw material is abundant all over the world. Lightweight aggregates produced from clay will have low density. The production processes of lightweight aggregate from clay involved crushing, mixing of raw materials, agglomeration and sintering process for hardening of the particles. Cement and charcoal were also used as additional raw materials in this study. The effect of sintering at temperatures between 900 °C and 1100 °C on density, specific gravity, particle shape of lightweight aggregates was examined. The samples were characterized by X-ray fluorescence (XRF) to determine the chemical composition and identify the element and substance present in the raw materials. The lightweight best aggregates obtained from this study consisted of 80 % clay, 10 % cement and 10 % charcoal (LWA 2). The 1050°C and 1100°C of temperature LWA 2 and LWA4 respectively was investigated to produce lightweight aggregate concrete. The lightweight aggregate LWA 2 of 1100°C had particle density of 1.896 g/cm3 and bulk density of 880 kg/m3 for coarse aggregates while lightweight aggregate LWA 4 of 1050°C had 1.639 g/cm3 and 440 kg/m3 of specific gravity and bulk density respectively. Lightweight concrete using the lightweight aggregates LWA 2 and LWA 4 was produced and the compressive strength and density of the lightweight aggregate concrete were studied up to 28 days. The average 28-day compressive strength was recorded as 14.76 MPa while, the average density was 1760 kg/m3 for LWA 2. By using LWA 4, the average 28-day compressive strength was 2.99 MPa and 1768 kg/m3 for density. It showed that LWA 2 have the best result.