According to the geological survey report, the geomorphic unit of Liangchang belongs to the piedmont alluvial proluvial inclined plain. The terrain is high in the east and low in the west, high in the north and low in the south. It is in the form of steps in some parts. The ground elevation is generally 129.85~133.72m, and the maximum elevation difference is 3.87m. During the survey, the buried depth of groundwater level was 7.50~8.00m. The geological stratification is as follows: the first layer is silty clay: yellowish brown, plastic, locally hard plastic. The soil is relatively uniform, containing a small amount of iron oxide and sand particles. The section is smooth, no response to shaking, and the dry strength and toughness are medium. This layer is widely distributed with uneven thickness, and the exposed thickness is generally 0.40-3.00m. The characteristic value of foundation bearing capacity is 160kPa. The second layer is pebble: yellowish brown, slightly dense~moderately dense, wet~saturated. The pebble is mainly composed of moderately weathered granite gneiss, in sub angular~sub circular shape, with a grain size of 2~10cm in general and 20cm in maximum. It is filled with about 35% medium coarse sand and clay, and is well graded. This layer is widely distributed with large thickness, and the exposed thickness is generally 9.20-19.20m. The characteristic value of foundation bearing capacity is 350kPa.
