EXPERIMENTAL AND ANALYTICAL STUDY OF THE RISING WATER LEVEL INFLUENCE ON THE STABILITY OF LABORATORY SCALE DAM USING SLIDE2 SOFTWARE

• Main Author: Kamaratih, Devi
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/67682
• Institution: Institut Teknologi Bandung

Mined tailings are generally in the form of mud or slurry and are stored in sediment ponds with dam construction. Mud or slurry is deposited first to separate impurities and water. Then the water will return to natural waters. This process of going in and out of the water causes a change in the water level in the sediment pond which makes the safety factor of the dam change due to the working forces such as pore water pressure, gravity, and the weight of the dam itself. The purpose of this study was to analyze the stability of the sediment pond dam against changes in water level. The research is done with two models, namely physical and analytical models. In the physical model, the dam on a laboratory scale is filled with water to a certain height and investigated the mechanism of dam failure due to sliding. The research was carried out three times for the sand material and twice for the clay material, each with different dimensions. Through laboratory experiments, a back analysis was carried out to obtain the cohesion and internal friction angle values that would be used as material properties in the Rocscience Slide2 software. The analytic model was carried out using the Bishop and Janbu limit equilibrium method under transient conditions. The results showed that as the water level in the reservoir increases, the safety factor decreases because the entry of water into the dam body will increase the pore water pressure which results in a decrease in the shear strength of the material so that it disrupts the stability of the dam. Then the safety factor with the Bishop method is smaller than the Janbu method. This means that the Bishop method tends to provide a more critical security value than the Janbu method.