STUDY ON RAPID EVALUATION OF SELF-WEIGHT COLLAPSIBILITY OF DEEP LOESS BASED ON STATIC PROBE TEST

Collapsibility is the most important factor restricting loess site construction. Loess field test is long in time and high in cost. This paper carries out the static cone peneration test in the New District in Lanzhou loess ground and the Jingyuan Yellow River high terrace loess area. It examines the taper cone tip resistance relation between frictional resistance along the depth of soil layer. It takes the original state collapsibility loess samples for indoor test. It is found that the coefficient of self-weight collapsibility measured in laboratory tests has a good linear relationship along the depth,and the relationship between the cone tip resistance and the cone side resistance. The coefficient of self-weight collapsibility measured by static penetration test is established. A method for rapidly evaluating self-weight collapsibility of loess site is put forward based on the results of static penetration test. Based on the above studies,the self-weight collapsibility of loess sites in the Jingyuan Yellow River terrace and Lanzhou New Area is evaluated,and the feasibility and accuracy of the method are verified.