摘要: |
A unified approach for profiling the effective yield stress of natural clays by in situ tests is presented. The empirical methodology is developed from statistical regression analyses of databases involving soft-to-firm normally consolidated clays and stiff-to-hard overconsolidated clay deposits that have been tested using the cone penetration, piezocone, dilatomater, vane shear, pressuremeter, and standard penetration tests. Similar trends are established for field test results in intact clays, whereas deviations occur for fissured materials. The interpreted profiles of the effective yield stress from in situ tests are quick, economical, and continuous, yet should be verified by companion sets of laboratory oedometer tests on high-quality specimens. The procedures are applied to two case studies involving natural clay deposits near Washington, D.C., where reference consolidation test data were available. |