TY  - EJOU
AU  - Deng, Cheng 
AU  - Zheng, Hui 
AU  - Gong, Liangyong 
AU  - Zhang, Rongping 
AU  - Wang, Mengqi 

TI  - An Improved Local RBF Collocation Method for 3D Excavation Deformation Based on Direct Method and Mapping Technique
T2  - Computer Modeling in Engineering \& Sciences

PY  - 2025
VL  - 142
IS  - 2
SN  - 1526-1506

AB  - Since the plasticity of soil and the irregular shape of the excavation, the efficiency and stability of the traditional local radial basis function (RBF) collocation method (LRBFCM) are inadequate for analyzing three-dimensional (3D) deformation of deep excavation. In this work, the technique known as the direct method, where the local influence nodes are collocated on a straight line, is introduced to optimize the LRBFCM. The direct method can improve the accuracy of the partial derivative, reduce the size effect caused by the large length-width ratio, and weaken the influence of the shape parameters on the LRBFCM. The mapping technique is adopted to transform the physical coordinates of a quadratic-type block to normalized coordinates, in which the deformation problem can easily be solved using the direct method. The stability of the LRBFCM is further modified by considering the irregular shape of 3D excavation, which is divided into several quadratic-type blocks. The soil’s plasticity is described by the Drucker-Prager (D-P) model. The improved LRBFCM is integrated with the incremental method to analyze the plasticity. Five different examples, including strip excavations and circular excavations, are presented to validate the proposed approach’s efficiency.
KW  - Radial basis function collocation method; irregular shape; excavation; elastic-plasticity

DO  - 10.32604/cmes.2025.059750