The packing and its application of 2-D circular discs

• Main Authors: Wang, Chen-Po, 王泉博
• Other Authors: Lin Jyh-Dong
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/72707049350238928249

碩士 === 國立中央大學 === 土木工程學系 === 84 === this research follows the theory of discrete element method built by Cundall (1971), and applies this concept to granular mechanics. the granularparticles are assumed as 2-D rigid circular discs. Comparison is made betweenthe penalty spring and the Hertz spring and the penalty spring is employed in this research. Penalty spring is found very efficient for the convergence of a granular system. Various spring stiffnesses are used to overcome the problem of squash spring which may occur in a system of various disc diameters. To simulate a nature deposit, this research develops an auto packing method which enhances the applicability of the developed code in engineering problem. In order to study the difference of mechanical behavior between the micro- scopic and macroscopic scales, examples simulate the rest angle and the activestate of sand are analyzed. For the same particle-size distribution curve, it is found that internal friction angle does not play a major factor as expected,In addition, for the active failure case, a regular packing shows a plane failure surface, while a random packing presents a smoothly curve plane, whichis similar to the assumption of a logarithmic spiral by Terzaghi and Peck (1967). This research shows that the 2-D circular discs can successfully simulate a granular system and engineering analyses.