Application of coupled elasto-plastic NMM–DDA procedure for the stability analysis of Prasat Suor Prat N1 Tower, Angkor, Cambodia

Abstract

There are many historic remains in the world and among them many masonry structures are in danger of collapse. To select suitable methods for restoration and preservation, it is important to evaluate the stability of masonry structures considering the interaction between foundation ground and masonry building, and accurate calculation of stress distribution inside the masonry structure is required. In the previous studies, NMM–DDA (coupled numerical manifold method and discontinuous deformation analysis) one of the discontinuum-based numerical methods was developed to satisfy these requirements and used for the stability analysis of Prasat Suor Prat N1 Tower in the Angkor monuments, Cambodia. However, the original NMM–DDA code treat only elastic bodies (for both DDA blocks and NMM elements) and cannot treat the failure of soil. Hence, in this study, the elasto-perfectly plastic constitutive law (Drucker–Prager model) was newly introduced to the original NMM–DDA code, and the model was verified by performing biaxial test numerically and comparing with analytical solution. The newly developed elasto-plastic NMM–DDA was applied to the stability analysis of Prasat Suor Prat N1 Tower. The simulation results were compared with the on-site observation/investigation and the applicability of elasto-plastic NMM–DDA was also discussed.

Keywords:

• NMM–DDA
• elasto-perfectly plastic constitutive law
• stability analysis
• masonry structure
• Angkor monuments in Cambodia

Acknowledgements

The authors are really grateful to Dr Shigeru Miki, Kiso-Jiban Consultants Co., Ltd., Dr Takeshi Sasaki, Suncoh Consultants Co., Ltd. and Dr Mitsuharu Fukuda, Taisei Geo Tech Co., Ltd., for their valuable comments and suggestions.