Ground Treatment of Airport by Heavy Cover Technique in Sulphate Saline Soil Region

The keypoint of ground treatment of airport in sulphate saline soil (SSS) region is to eliminate salt heaving. Concept of dangerous point (DP) was brought forward. Based on the fact that load can control salt heaving effectively, ground treatment by heavy cover technique was put forward. Experiments about salt heaving under different loads were carried out to study the restraining effect of load, and a salt heaving formula was deduced out which can calculate salt heaving rate with three parameters: compaction degree, saltness and load. Three typical dangerous points including compaction degree dangerous point (CDP), saltness dangerous point (SDP) and water dangerous point (WDP) were analyzed. Control guideline ground treatment was discussed, and the method and flow chart for calculating the minimun load and thickness was given, calculatation indicates that 50 kPa is almost enough to control salt heaving, the minimun thickness is about 2 meters with grit material for covering.