Modified Similitude Law for Pseudodynamic Test on Small-scale Steel Models

철골 축소모헝의 유사동적실험을 위한 수정된 상사법칙

  • Kim, Nam-Sik (Technology Research Center of Hyundai Engineering and Construction) ;
  • Kwak, Young-Hak (Yooshin Engineering Corporation ) ;
  • Chang, Sung-Pil (Dept.of Earth Environment System Engineering, Seoul National University)
  • Published : 2003.12.01


Although there are several experimental techniques to evaluate the seismic behavior and performance of civil structures, small-scale models in mast of physical tests, instead of prototypes or large-scale models, would be used due to a limitation on capacities of testing equipments. However, the inelastic seismic response prediction of small-scale models has some discrepancies inherently because the similitude law is generally derived in the elastic range. Thus, a special attention is required to regard the seismic behavior of small-scale models as one of prototypes. In this paper, differences between prototypes and small-scale models pseudodynamically tested on steel column specimens are investigated and an alternative to minimize them is suggested. In general, small-scale models could have the distorted stiffness induced from some experimental errors on test setup, steel fabrication and so on. Therefore, a modified similitude law considering both a scale factor for length and a stiffness ratio of small-scale model to prototype is proposed. Using the modified similitude law to compensate experimental errors, the pseudodynamic test results from modified small-scale model are much improved as compared with the results of prototype. According to the pseudodynamic test results of small-scale steel models, it can be concluded that the modified similitude law proposed could be effective in simulating the seismic response of prototype structures.


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