Pavement Engineering Parameters for Thai Collapsible Soil

摘要

This paper presents an investigation of the potential of collapsing soil or loess from Thailand for possible use as a pavement material or subbase. Earlier studies indicated high CBR values for well-compacted material. The collapsing soil is classified as silty sand, with a slight to moderate degree of colkpse index. Thai collapsible soil samples were tested generally in the compacted condition (Modified compaction) at optimum moisture content and maximum dry density. Consolidated Isotropic Undrained (CIU) triaxial testing with pore water pressure monitoring was performed on back-saturated samples to quantify the permissible stress states for resilient modulus testing. The resilient modulus of the soil was found to be stress dependent and trends agreed reasonably well with the current AASHTO empirical equation for the resilient modulus of sand.