Experiences in the use of the Marchetti dilatometer in the characterization and countermeasures for landslides in Costa Rica

Abstract

The geological and climatic contexts of Costa Rica make the country highly vulnerable to the occurrence of landslides. Given the latter, the proper geotechnical characterization of a given landslide is key in the search and design of a repair solution. This involves both an accurate definition of failure mechanism and the definition of geometry. However, the qualitative and quantitative tools, such as the experience of geologists, geotechnical engineers, and traditional tests like SPT, or geophysics, tend to generate scattered or inconclusive information that must be treated with care. Under this scenario of uncertainty the Marchetti dilatometer DMT was chosen to be implemented, given that this is a test that allows the study of the deformability, strength, and stress state of the soil. This makes possible the performance of a better soil characterization and the identification of the failure surface geometry, optimizing the design and implementation of the landslide stabilization and repair solutions. Three successful study cases are presented where the DMT was implemented to identify the geometry of the corresponding failure surface to develop the landslide repair from design to construction.