SAFETY EVALUATION OF MASJED-E-SOLEYMAN ROCKFILL DAM, DURING CONSTRUCTION and FIRST STAGE IMPOUNDING

Developed excess pore water pressure in the clay core of zoned rockfill dams during the construction period and first stage impounding, may lead to initiation or progression of hydraulic fracturing. The ability to predict the development and dissipation of these pore pressures is important in assessing the performance of such structures. This phenomenon also depended on the arching effect status of the core zone due to difference in stiffness of materials. In this paper a case study of MASJED-E-SOLEYMAN HEPP central clay cored rockfill dam (located in Iran) with the height of 178 meter, will be considered by performing numerical analysis with FLAC ver 4.0 code. The main purpose of this research is to predict pore pressure coefficient and arching ratio parameters. Interaction of these parameters is to be considered. A non-associated strain softening elasto plastic model has been used to study the stress-deformation behavior of dam. For evaluation of safety of MES dam, instrumentation process is simulated in the numerical model and the calculated results validated by comparison with field-measured data. The results show that: • Implemented constitutive model has good precision to simulate dam behavior and to predict its future performance. • Deformations due to first impounding of dam reservoir can lead to changing of dam safety