OPTIMAL LOCATION OF BERM IN EARTH AND ROCKFILL DAMS

Abstract

In dams the location of berm is usually governed by traffic requirements. Recently, it has been pointed. out that the stability of the dam section can be improved by providing a berm. The present work is an attempt to study for the optimal location of berm in,eart,t and rockfill dam. The study has been carried out with changing the berm locations considering (i) a berm on either upstreaia or downstream side and (ii) one perm eac~t on both sides. Investigations were also made for a no oern case.. ... ,, For all the situations the width of berm is kept constant and equal to 25m. The slopes for different situations are adjusted such that tae amount of the. fill remains same. Computerised numerical calculations in static and dynamic conditions are made by the finite element technique using four noded isoparametric elements. The dam material is presumed to be linearly elastic. aid' isotropic. In static analysis, different dam sections have" been studied for two types of •load conditions (i) the gravity loading and (ii) the gravity loading in conjunction with hydrostatic loading. Full-reservoir condition was investigated for the later case. The difference in dis-placement and stress states in all tcie sections have, been studied.