ObjectiveIn order to study the mechanics characteristic of colluvial deposits of collapsing gully, soil simulation of the collapsing had been made and the unconfined compressive strength was measured.
MethodTwo methods to mix the sand and soil and different sand content were taken.
ResultThe results showed that unconfined compressive strength reducted along with the reduction of sand content because of the lesser axial stress. From 0% to 100% of sand content, unconfined compressive strength reduction from 71.1 kPa to 14.6 kPa. The specimen mixed sand to soil with separated layer destroyed seriously and the strength was smaller result to the unstable substratum. The highest strength occurred to the specimen which was low sand content and mixed uniformly.
ConclusionMixing sand dramatically reduces the unconfined compressive strength of soil in collapsing gully. Under the same sand content circumstances, specimen mixed uniformly has a high strength and brittle failure at the end of test.