Application and error improvement of large mass method used in DEM-based multi-support excitation analysis
Xu Lingling1Ye Jihong1Xue Suduo2
1. Key Laboratory of Concrete and Prestressed Concrete Structure of Ministry of Education, Southeast University, Nanjing 210018, China
2. Beijing University of technology, Beijing 100124, China
To solve the problem of multi-support excitation of DEM, large mass method (LMM) is introduced into the discrete element method (DEM). Based on proposed member discrete element method (MDEM), the theoretical formula of LMM is derived and the corresponding computing program is compiled. The theory indicates that the error of LMM depends on mass proportional damping coefficient, and the error increases as it becomes larger. Thus, the article presents herein the improved large mass method (ILMM) according to the correction formula acquired from earthquake wave's acceleration time-history curve. Numerical model of 40m-span K8 single-layer reticulated spherical shell is established and seismic response analysis is performed. The value range of the damping and large mass in the DEM is determined first. Then the dynamic time-history analysis is carried out using relative motion method (RMM), LMM and ILMM respectively. The comparative results show that ILMM agrees well with the RMM and the error is reduced significantly. Furthermore, the practical applicability and accuracy of ILMM in the MDEM are verified.
大质量法在基于离散元法多点激励分析中的应用和误差修正[J]. 土木工程学报, 2016, 49(S1): 32-36.
Xu Lingling Ye Jihong Xue Suduo. Application and error improvement of large mass method used in DEM-based multi-support excitation analysis. 土木工程学报, 2016, 49(S1): 32-36.
