Performance of Concrete Gravity Dams with Height 50m and 75m based on Incremental Dynamic Analysis

Abstract

This paper discusses the performance of concrete gravity dam with a height of 50m and 75m is studied by using the incremental dynamic analysis (IDA). The IDA curves were develop based on seven ground motions which fulfil the criteria of i) the distance of near field is less than 15km, (ii) the earthquake magnitude is greater than 5.5 and (iii) the PGA is equal to or greater than 0.15g. Seven of ground motions were converted to response spectrum and scaled according to the characteristic of the soil type for development of elastic response spectrum. Referring to Eurocode 8, elastic response spectrum was developed based on soil type B. By using IDA method, the limit states of the dam which are yielding and ultimate state are identified based on the cracking schemes. The displacement of yielding state for 50m height of dam is 14.60mm and 23.18mm for 75m height of dam. Meanwhile, the ultimate state is 23.18mm and 52.05mm for 50m and 75m height of dam respectively. The results show a greater damage occurred on higher dam and allow us to study the performance of dam with various height under seismic loadings.