Method for estimating at-rest lateral pressure coefficient of coarse-grained soils
摘要
The at-rest earth pressure coefficient K0 is a basic mechanical parameter of soils. So studying K0 of coarse-grained soils is of important theoretical value and practical significance in geotechnical engineering. At present, there are few apparatuses and methods applicable for measuring K0 of coarse-grained soils. Therefore, an accurate and reliable empirical formula for K0 has a strong application in the actual earth-rockfill dams. For obtaining the reliable estimation formula for K0 of coarse-grained soils, a number of K0 tests and CD triaxial tests for a sandy gravel and a rockfill are performed by using the specially large-size K0 apparatus and large-size triaxial apparatus, respectively. Based on the results of K0 tests on all specimens, the relationship between K0 and vertical stress σ’v for the coarse-grained soils proposed by the authors is verified. By combining the relationship and triaxial test results, an empirical formula is obtained, which can well describe the relationship between K0 and stress state under an arbitrary consolidation condition based on the effective angle of internal friction φ′. Finally, the proposed formula is verified by using K0 test data.