Unit 1
Earth dams – types of dams – selection of type of dam based on material availability – foundation conditions and topography. Design details – crest, free board, upstream and downstream slopes, upstream and downstream slope protection – central and inclined cores – types and design of filters. Seepage analysis and control – seepage through dam and foundations – control of seepage in earth dam and foundation. Stability analysis – critical stability conditions – Evaluation of stability by Bishop’s and sliding wedge methods under critical conditions.
Unit 2
Construction techniques – methods of construction – quality control. Instrumentation – measurement of pore pressures. Earth pressure theories – Rankine’s and Coulomb’s earth pressure theories for cohesionless and cohesive backfills – Computation of earth pressures for various cases – inclined – with surcharge – submerged and partly submerged – stratified backfills.
Rigid retaining structures – active and passive earth pressures against gravity retaining walls – Surcharge – Computation of earth pressures by Trial wedge method – a mathematical approach for completely submerged andpartly submerged backfills – Importance of capillarity tension in earth pressure.
Graphical methods of earth pressure computation – Trial wedge method for coulomb’s and Rankine’s conditions, for regular and irregular ground and wall conditions – Rebhan’s construction for active pressure – Friction circle method – Logarithmic spiral method.
