Tangent modulus method based on in-situ pressuremeter tests and its preliminary validation

The tangent modulus method is a method which is based on the plate loading tests to obtain the tangent modulus of the soil under different load levels, and uses the tangent modulus into the layer-wise summation method for calculating foundation settlement. It is one of the best methods for settlement calculations at present, which can overcome the adverse effects of sampling disturbance and reflect the nonlinearity of foundation settlement. However, the deficiency of the tangent modulus method based on the plate loading tests is that the plate loading tests need a heavy workload and cannot reflect the characteristics of soil in deep layers. While, compared with the plate loading tests, the pressuremeter tests take the advantages of simple operation and can test the soil with different depths, which can be said as simple and practical in-situ tests. Therefore, in order to further develop the tangent modulus method, one method in which the pressuremeter tests are used to obtain the parameters of the tangent modulus method is studied, and its feasibility is verified by the results of four plate loading tests with different sizes, which are tested in one fines sand foundation of Texas A&M University riverside campus. The results show that the calculated results of settlement curve of four plate loading tests with different sizes agree with the experimental ones, which preliminarily verifies the feasibility of the tangent modulus method based on the in-situ pressuremeter tests.