Mechanism model test of interaction between bucket foundation and soil subjected to torsional resistance

Based on the model test, the failure mechanism of bucket foundation subjected to torsional resistance was investigated with different draw radio. The results show that the curves from model test are in good consistency with numerical calculations. The rotation angle of bucket foundation is increased by the increasing of torsional loading with almost linear relationship. At initial stage, the remarkable torsional loading variety leads to slight increase of rotation angle. When the imposed loading reaches a stable value, slight enhancement of torsional loading can result in marked variety of rotation angle with almost linear relationship. The inside and outside earth pressures of bucket foundation are axial symmetry. The inside earth pressure of foundation is increased from top to bottom with almost identical outside earth pressure. The annulus shear failure at the bottom of foundation is generated by torsional loading. The rotated shear deformation around the bucket foundation is generated with foundation axis as centre, and propagates around the foundation.