RKPM2D-EQ Large-strain Computational Framework

by Ahmed Elgamal, Jiun-Shyan Chen, Zhijian Qiu, Jonghyuk Baek, Tsunghui Huang, Haoyan Wei, Jinchi Lu

Acknowledgements: The research was primarily supported by the Pacific Earthquake Engineering Research Center (PEER). This support is greatly appreciated (


An effort is made to bring the capabilities and advantages of the meshfree method within a dedicated open-source framework for use in earthquake engineering applications.

This effort builds on the open source RKPM-based meshfree computational framework developed by Prof. JS Chen and coauthors (Chen et al. 2013, 2017a, b; Chen and Belytschko 2015; Huang et al. 2019) for linear static analysis. The open-source codes RKPM2D (Huang et al. 2019; is available at:

Currently, the original RKPM2D framework has been updated with the following capacities (i.e., RKPM2D-EQ): 1) dynamic analysis, 2) material (soil) nonlinear elasto-plastic modeling, 3) periodic boundary, 4) large-strain analysis module, and 5) multi-zone material representation. As such, 1) site response analysis; 2) large-deformation dynamic analysis of a simple earth dam configuration under earthquake loading; 3) dynamic analysis of a building resting on soft clay, are shown below, to demonstrate the capabilities of this extended computational framework (i.e., RKPM2D-EQ).

Download RKPM2D-EQ computational framework below:
RKPM2D-EQ computational framework (updated 10/17/2022)

Application Examples

1. Site Response
2. Large-deformation dynamic analysis of an earth dam
2.1 Configuration


2.2 Computed results

3. Dynamic analysis of a building resting soft clay
3.1 Configuration


3.2 Computed results


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