Abstract: The expansive soils within a water transmission project limits were extensively studied with site test pits sampling, laboratory mechanical property testing and CT scanning of the failure planes of the samples collected from the test pits. These test results indicate that the landslide failure modes in the strong expansive soils are mainly related to the failure mode that controlled by the strength of the fissures. Based on the failure mode characterization, the feasibility of the umbrella anchor in the mitigation of the landslides in strong expansive soils, installation procedure are discussed in the paper. The construction monitoring data indicated that the mitigation was successful.

Key words: Umbrella Anchors, Landslide in Expansive Soils, Mitigations