Abstract: Expansive soil stratum is featured with deep fissure development which brings about stability problems to high slope of expansive soil in excavation process. Commonly used reinforcement or protective measures for temporary high slope of expansive soil are of poor adaptability and low economic benefit. Prestressed umbrella-shaped anchor is a new solution for the reinforcement of temporary expansive soil slope. In order to solve the stability problem in the excavation of expansive soil slope in Water Resources Allocation Project in North Hubei Province, we conducted field test of prestressed umbrella-shaped anchor and evaluated its popularization value in practical application. Research result demonstrates that prestressed umbrella-shaped anchor is of fast construction and large resistance against pull-out force, hence effectively controlling deformation development and ensuring slope stability. According to the safety monitoring data of slope, we verified that umbrella-shaped anchor is of good application and popularization values in the rapid reinforcement of expansive soil slope.

Key words: umbrella anchor, water diversion project in north Hubei Province, expansive soil, slope reinforcement, field test