EVALUATION OF DETERMINING SEISMIC COEFFICIENT BASED ON NEWMARK DEFORMATION ANALYSIS IN CIAWI DAM

• Main Author: Qinthara Aghnat, Muhammad
• Format: Theses
• Language: Indonesia
• Subjects: Teknik sipil
• Online Access: https://digilib.itb.ac.id/gdl/view/71576
• Institution: Institut Teknologi Bandung

Evaluation of dynamic stability in embankment dams is commonly carried out using pseudo-static analysis with the limit equilibrium method (LEM) because of its practicality and ease of understanding. The determination of the seismic coefficient which is applied to the potential slip surface is an important thing to consider. In Indonesia, this procedure has been regulated in the construction and design guidelines (Pd T-14-2004-A) regarding the analysis of the stability of the embankment type dam due to earthquake loads. However, this guide was developed based on the earthquake-resistant design guidelines in Japan (2000) which have different seismic and geological conditions with regions in Indonesia. The evaluation of the determination of the seismic coefficient is performed on the Ciawi Dam by developing the method proposed by Ghanbari and Davoodi (2010). The determination of the seismic coefficient considers two factors, the reduction factor for the maximum horizontal acceleration of the surface and the amplification factor due to the effect of dam geometry. Parameter ? determination is carried out by comparing the seismic yield coefficient to the maximum horizontal surface acceleration resulting in permanent deformation of 0.3 meters obtained from the Newmark deformation analysis. Parameter ? were obtained from the trend of the value of the seismic coefficient of the dam elevation with the assumption that it is linear. To obtain the trend of the seismic coefficient in the function of elevation, variation of the slip plane elevation performed at Y=1H; 0.75H; 0.5H, and 0.25H as the method used in the pseudo-static analysis with the limit equilibrium method regulated in Pd T-14-2004-A. The seismic coefficients generated from this study are compared with the results from several previous studies and seismic design guidelines in other countries. Based on the evaluation performed, the seismic coefficient obtained in this study has a relatively low magnitude compared to the results of Pd T-14-2004-A. Thus, the seismic coefficient determination regulated in Pd T-14-2004-A can be considered conservative to be used as a guideline for the dynamic stability design of the embankment dam.