Summary: | 碩士 === 國立臺北科技大學 === 土木與防災研究所 === 98 === Observed in the wild exploration of the particulate material, such as: gravel, because the force of rock particles and particles of gravel resulting from indirect contacts of the contact stress concentration point of contact with the gravel to reach the center, causing multiple rupture surfaces intersect, coaxial, while the present radial (star) break; rupture plane intersecting the central axis, by a general geological statistical methods to obtain the amount of broken shaft arrangement direction (the direction of exposure); For a long time, this contact with the general direction of the maximum contact force as a regional direction, or so-called maximum palaeo-stress direction, in order to understand particulate material under pressure, when the maximum contact force concentrated in one point, when the direction of its rupture would parallel the greatest contact force direction, or will they will have a little angle of deviation, this reasoning there are still controversial. In this study, micro-particle contact to be analyzed by analysis of triaxial tests, consistently cutting simulation, changing the material parameters and so on, which will help to understand the deformation behavior of granular materials.
In this study, discrete element method PFC 3D simulation of granular materials, access to the direction of the force, numerical simulation of granular materials by squeezing, the particle direction and the contact force between the contact size conversion process. Set different parameters and different micro-and coherent form, observe the behavior of particle contact and contact force changes, including estimating the direction of maximum contact force and the particle contact angle of the direction of the process of change with the strain the situation.
When the specimen to simulate triaxial tests and the proper test, the contact between the behavior of particles should be subject to different variables and different parameters studied. Results indicate that the contact force and contact direction and the size of the specimen is directly related to the direction of rupture.
|