Displacement and Rotation Measurements of Particles in Shear Zone

In this study, direct shear tests were performed by using the layered product of aluminum rods that a granular material is simplified to investigate the displacement and rotation of particles in shear zone. Then, the displacements each aluminum rods during the shear were observed by the technique of image measurement, and the local displacements and rotations are compared and examined with each particle size tests. From the observed results, it was found out that the tendencies of the shear stress- shear displacement relation and vertical displacement-shear displacement relation were similar to the behavior in the direct shearing of the actual sand material well in the deformed aluminum rods aggregate during the shear. A clear boundary plane can be seen in the distribution charts of the horizontal and vertical displacements of the tracking points in the adjacent area of the shear plane, and the formation of the shear band could be confirmed caused by the progress of the shear failure. The rotation of particles were active in the inside area of the boundary plane as compared with the un-dynamic particles in the outside area. Then, the width of the shear band was about 10-15 times of the average particle diameter. This result was consistent with the results measured in the direct shear tests of Toyoura sand (the average particle diameter is 0.19 mm) in the previous study.