Sarıçay Dam: a case study on in-depth seismic evaluation, deformation modulus and key geotechnical parameters

Abstract

The Sarıçay Dam project in southwestern Türkiye integrates advanced geotechnical evaluation methods for building dams in areas with challenging geology and seismic activity. This study foregrounds an in-depth analysis of deformation modulus, the efficacy of consolidation grouting and shear strength parameters. It addresses critical issues such as encountering faults during construction and their mitigation, with the ‘observational approach’ being adopted to inform strategies and solutions and/or any modifications to these, including any design aspects. The appropriate selection of the deformation modulus and understanding its enhancement through consolidation grouting remain long-standing issues in geotechnical engineering. The comprehensive analyses of the deformation modulus revealed that certain empirical equations yield results comparable to those from in situ tests, although some may significantly overestimate; hence, correlating these tests with geophysical methods is crucial for accurate evaluation. Moreover, the deformation modulus results, derived from both rock pressuremeter and dilatometer tests on similarly characterized rock masses, displayed a notable comparability, despite the inherent scatter attributed to rock masses’ heterogeneity and anisotropy. The findings revealed that consolidation grouting, despite its minimal effect on increasing the deformation modulus (4–18%), plays a role in reinforcing the foundation by filling joints and fractures. The research experiences and outcomes on this project will contribute to the knowledge base for future dam projects.