Abstract
Ultra-soft clay generally has properties such as a large water content, a large void ratio, a large liquid index, companied with physical properties of a small coefficient of consolidation, a low soil strength and a small inner friction angle in quick-shearing test. Under a preload of 80 kPa, the ratio of settlement to soil height reaches 50%, much larger than that for common soft soil. When the consolidation pressure is less than 200 kPa, large changes occur in deformation and void ratio accompanied with a large consolidation rate. When the consolidation pressure exceeds 200 kPa, the rate of change for deformation and void ratio variation tends to be slow.
