Full-scale test studies on prevention of frost damage for retaining wall reinforced with geotextile

In the Hetao irrigation Area, Inner Mongolia Autonomous Region, China, canal irrigation has a very important effect on the agriculture, The climate is very cold and dry in winter. The problem of frost action damage is widespread in hydraulic construction in the area This paper presents full-scale test studies on prevention of frost damage for a 2m high retaining wall reinforced with geotextile. The facing panel was made up of reinforced light precast concrete slab. The horizontal displacement of the facing panel, the strain of geotextile, and the soil temperature and moisture content were measured during the winter of 1993-1994 (the Frost Index FI=837 degrees Cday). Steel wires were used to measure geotextile strains in the retaining wall under winter conditions. The test results indicated that the displacement of the facing panel comprises of horizontal frost heave and unfrozen-soil compressive deformation of backfill. In the 0 similar to-0.3m range near the facing panel frost heave occurred. In about the 0.3 similar to 0.9m range from the facing panel the soil was compressed before freezing and heaved alter Freezing. Outside that zone the soil was compressed. The horizontal frost heave of backfill was 15 similar to 30mm, while the horizontal displacement of the facing panel measured only 6mm because the frost heave was partially counteracted by the compressive deformation of back unfrozen soil. Near the facing panel, the frozen soil formed a thick solid mass with great rigidity and strength and was approximately equivalent to a pseudo gravity retaining wall which resisted the frost heaving action of back soil.