ABSTRACT
Embankment dams are critical infrastructure for water storage, irrigation, and flood control, often located in seismically active regions. This study examines the seismic performance of Chang Dam, a zoned embankment dam damaged during the 2001 Bhuj earthquake. Static, pseudo-static, and dynamic analyses were conducted using numerical modeling to assess slope stability and the influence of material nonlinearity. Seepage analysis was performed to establish the phreatic surface, followed by in-situ stress initialization. The factors of safety under static conditions were 2.05 and 1.56 for the upstream and downstream slopes, respectively. Under pseudo-static analysis with horizontal seismic loading, the FoS decreased to 1.49 (upstream) and 1.21 (downstream). Dynamic analyses showed that linear models underestimated stress compared to the nonlinear model. Due to nonlinear effects, vertical stress increased by 15.6%, and horizontal stress by 6.6%. Similarly, deformation are also increased by a margin of 8% due to nonlinear effects. The findings highlight the importance of incorporating nonlinear dynamic analysis in the seismic evaluation of embankment dams.
