Investigating the Influence of Earth Dam Shell MaterialStiffness on Dynamic Responses Using Perfectly MatchedLayer (PML)

Nowadays with advances in analysis tools, the accuracy of the estimated deformations of earth structures hasgreatly improved, but still, there are some limitations in predicting appropriate responses. One source ofinaccuracy in results is the reflection of the scattered wave from considered numerical model boundaries. Tosolve this matter, some boundary conditions were developed. Perfectly matched layer is one of the recentlyintroduced boundary conditions which able to eliminate unwanted scattered waves from numerical modelswithout any considerations about wave direction or frequency content and amplitude of it. PML is a widelyadopted non-reflecting boundary treatment for wave simulations. This study investigates the effect of earth damshell materials stiffness on the final responses. A section of Masjid Suleiman embankment dam with ۱۷۷mheight was considered and a set of earthquake acceleration time history was applied. For dynamic analysis,IDAMP program was employed. IDAMP is a time domain finite element program which can simulate a semifiniteenvironment by using perfectly matched layer (PML). All considered time histories were applied at thebase of the models in the boundary of the soil and PML. The effect of soil-structure interaction has beenconsidered in direct method by simulating wave propagation in a semi-infinite environment. The results of dambased on the semi-infinite foundation was compared with the same dam based on the foundation with rigidboundaries. The results show that PML can simulate the semi-infinite environment perfectly and absorb thescattered waves without any reflections. For more investigations, some models with different stiffnesses getanalyzed.

کلیدواژه ها:

Perfectly Matched Layer ، Dynamic Analysis ، Embankment Dam ، Finite Element Method ، IDAMP