Engineering Geological and Geotechnical Assessment of the Foundation of Yaragol Gravity Dam – A Case Study form India

Abstract

Engineering geological and geotechnical assessment of the dam foundation are essential for the design of the dam to ensure safety. At the southeastern part of Karnataka, Yaragol gravity dam is being constructed, which is designed based on site geomorphological and geological conditions and economic reasons. This paper discusses the results of the engineering geological and geotechnical investigations that have been carried out at the foundation levels of the dam. The dam foundation is composed of foliated gneiss and granite gneiss belonging to Archean to Paleoproterozoic age with intrusive dykes. This study is based on field and laboratory investigations, surface discontinuity mapping, drilled borehole data and in-situ shear testing. In-situ shear parameters of rock-rock interfaces and concrete-rock interfaces were conducted for the evaluation of dam stability against sliding. The classification and rock mass quality of the dam site is assigned using the rock mass rating (RMR) for all the 19 blocks and allowable bearing pressure (qallow) is assessed based on rock types and RMR. At all the blocks foundation, geological defects were mapped and analyzed and treated with suitable engineering measures. Based on structural features mapped, curtain grouting and consolidation grouting is recommended.

Study on the deformation law of the construction of the cutoff wall of the reservoir

“…The field monitoring and analysis of the cutoff wall in Daning Reservoir is a typical geotechnical safety monitoring and analysis. At present, the safety monitoring and data analysis method in geotechnical engineering is widely used [ [14] , [15] , [16] , [17] ], its performance is closely related to the design scheme, such as the verification and perfection of the arch dam test load method theory [ 18 ], verification of the stress and strain characteristics and calculation assumptions of mass concrete [ [19] , [20] , [21] , [22] ], analysis and determination of permeability and deformation of cutoff wall [ [23] , [24] , [25] ], stability verification of the foundation pit supporting structure [ [26] , [27] , [28] ].…”