Soil Mechanics and Foundation Engineering

The contact problem is examined of the effect of torque on an annular plate lying on an elastic layer. The practical analog of this problem is the problem of determining the tilt of a high-rise structure resulting from wind load. The problem is solved using the Ritts and orthogonal polynomial methods. Results are presented of calculations of annular plate rotation angles in response to torque.

Soil samples with different organic matter contents and their geotechnical index properties were determined. With an improved direct shear creep apparatus, the rheological characteristics of the soil samples were tested under stepwise loading, and the strain-time curves (creep curves) under different loads were obtained. Based on the Nishihara model, a new nonlinear viscoelasto-plastic soil rheological model (improved Nishihara model) was proposed by introducing a nonlinear Hooke element, which is capable of reflecting the rheological properties of artificial soft clay and natural soft clay. The results of the fitting indicate that the organic matter content is an important factor in the creep behavior of soft clay, and there is a good correlation between the organic matter content and the rheological model parameters.