Design and analysis of new direct shear apparatus based on parallel mechanism technology

With the key point of parallel mechanism, a method of design and analysis of large direct shear apparatus is presented which has three-dimensional translation. Based on the problems of traditional geotechnical synthetic materials direct shear test, the application-oriented design principles of direct shear apparatus is given, and synthesis a parallel drive institution. Based on this analysis, a large direct shear apparatus which can realize three-dimensional translation is designed. According to influence coefficient method, the direct shear test is analyzed, the relationship between drive mechanism and shearing motion of soil samples is built, and the kinematic and dynamic model is obtained. Combined with related specification, the structure parameters are established. The performance distributions of displacement, velocity and force are depicted in test process, and the anisotropic mechanical properties of geotechnical synthetic materials are analyzed. The results can be used for designing and producing of this new equipment, and also lays a foundation to apply parallel mechanism technology in traffic transportation.