Abstract: The Thar Coalfield area in Pakistan is a widely developed with collapsible sandy soil, which is a typical special soil for the engineering construction in this area. From the perspective of geotechnical engineering investigation case history, the causes and types of the collapsible sandy soil and the geophysical characteristics of geotechnical and electrical layers of TEL 1×330 MW Power Plant Project in Thar Coalfield Block II, Pakistan was analyzed, the engineering characteristic of the collapsed-sand foundation is evaluated by using the results of laboratory collapsed-sand and the in-situ immersion load tests. This paper proposes the engineering treatment measures and predicts the possibility of selfweight collapsibility, and the correction coefficient β of the sand collapsibility and the principles and measures of the foundation treatment in this area are proposed, the scheme of foundation and the problems in the geotechnical construction are also proposed according to the characteristics of the site.

Key words: Collapsible Sand, Self-Weight Collapsible Coefficient, Immersed Plate Load Test, Collapsible Grade, Cast-In-Place Bored Piles