The comparison of physical and mechanical properties of sand in Sedau and Obel-Obel Village

Abstract

The research was conducted in two regencies: Sedau Village in West Lombok Regency and Obel- Obel Village in East Lombok Regency. The two research sites are areas with potential sand wealth, with many sand mining companies operating. The sand mining company at the research site is expected to implement good mining practices which pay attention to mining design safety. Geotechnical recommendations on slope dimensions with a good safety factor value are required in making a mining design. Several factors affect a rock’s geotechnical properties. These factors are physical and mechanical. In this study, a comparison was made between the physical and mechanical properties of sand at two locations, which aims to compare rock characteristics and become a reference for geotechnical recommendations in the area. The research method used was sampling and testing in the laboratory. The results showed that the porosity value in Sedau Village was 0.102 and Obel-obel Village’s was 0.09. The average water content value in Sedau Village was 6.567%, and the average water content value in Obel-Obel Village was 8.233%. The specific gravity value of sand in Sedau Village was 3.75 gr/cm3, and that in Obel-obel Village was 3.75 gr/cm3. The compressive strength of sand in Sedau Village was 0.137 Mpa, and the compressive strength of sand in Obel-obel Village was 2.32 MPa. Based on the laboratory testing results, the influencing factors were analyzed, namely the location of its formation and the different processes of sand sedimentation in Sedau Village and Obel-obel Village.