IMMERSION TEST RESEARCH ON NEGATIVE FRICTION RESISTANCE FOR SOIL DISPLACEMENT SCREW PILES IN SELF-WEIGHT COLLAPSIBLE LOESS FOUNDATION

Soil displacement screw(SDS)piles have been widely used in engineering fields, but the theoretical basis of design for SDS piles in collopsible loess zones was still absent. In order to explore the mechanical properties under immersion states, a full-scale immersion test of mechanical properties for SDS piles was carried out. The negative friction characteristics of two-way SDS piles along pile shafts under immersion were obtained.