Static analysis of RCC dams constructed on weak foundations

ABSTRACTMSc ThesisSTATIC ANALYSIS OF RCC DAMS CONSTRUCTED ON WEAK FOUNDATIONSMuhammet ÇİÇEKFırat UniversityGraduate School of Natural and Applied SciencesDepartment of Civil Engineering2007, Page: 114This design is proposed for RCC dams to take full advantage of the characteristics of this material.The basic features of this design are: a symmetrical cross section; a watertight upstream facing; no internaldrainage of the dam body; and the use of a lean RCC. The main advantages of this design are: low stresses inthe dam body and foundation; low cost of the hardfill; and, greater safety than gravity dams, particularly forearthquake conditions.In this study, hardfill dams constructed on weak foundations having different soil strength wereinvestigated linear elastic response under the static loads. The dam and foundation domains were assumed aslinear elastic and modeled with finite element technique. The foundation strength was computed in term of(Et/Eb) ratio of the dam elasticity modulus. Analyses were obtained for 0.125, 0.25, 0.5 and 1.00 of the Et/Ebvalues. Upstream and downstream slopes are taken as (0.6y/1.0d), (0.7y/1.0d), (0.8y/1.0d). Moreover, damheights were selected as 30, 60, 90 and 120 m for investigating the effect of hardfill dam height. Analyseswere made for empty, semi-full and full conditions of reservoir for investigating the effect of the hydrostaticpressure.Variation of minimum and maximum principal strength occurred at the dam body and foundationinterface were investigation depending on dam slope, dam height and Et/Eb values. In addition to this,displacements were investigated likewise. Results were obtained at dam body and dam-foundation interfaceand equations belong to these were presented. Thus, preliminary planning of hardfill dams constructed onweak foundations will be made using presented equations.Keywords: Hardfill dam, RCC, weak foundation, static analysis, gravity dam.