Effect of beach sand addition on Singgora roof tile properties

Singgora roof tile is the traditional roof tile that widely uses before in Kelantan and Songkla, Thailand. Singgora roof tile can easily break due to the low strength. The aim of this study was to investigate the physical and mechanical properties of Singgora roof tile due to effects of beach sand addition. This research examines development manufacturing process of singgora roof tiles by fabricating into bar samples. In this research, the particle size of raw singgora clay was controlled to 500 µm while the particle size of beach sand was controlled at 710 µm. The element and phase composition of raw materials were characterized by using XRD. The clay are divided into original clay (OR) and industrial clay (IR). The industrial clay was added of salt by the industry. The clay was added by beach sand at composition of 0, 10 and 20 wt.% and were labelled as OR0, OR10 and OR20 or IR0, IR10 and IR20 for original clay and industrial clay, respectively. The samples were fired at 800 °C for 16 hours. The morphology characteristic was carried out by using SEM. The effect of beach sand addition on drying shrinkage, density, porosity and bending of samples were identified. After firing, the addition of beach sand had decrease the modulus strength from 3312.82 N/mm2 into 1859.54 N/mm2 and 1334.53 N/mm2. The bending strength also decrease from 7.15 N/mm2 to 3.58 N/mm2 and 2.98 N/mm2 due to beach sand did not melted during firing. Other than that, the addition of salt in the clay had cause the break of sample during firing. In conclusion, the result shows the addition of beach sand need a high firing temperature to make sure the sand grain to melt and bind to clay matrix. However, more research and study about Singgora roof tile should be done to obtain the high quality tiles with a high strength but low in density.