Research on the Overstrength Performance of Lateral Force-Resisting System of Guangzhou West Tower Based on Story Overturning Moment

The factors of the building's structure's overstrength performance need to be researched to decrease the large amount of the structural materials and the investments caused unreasonably by the overstrength performance. Taking the Guangzhou West Tower as an example, the main reasons why the Guangzhou West Tower model structure was not damaged after encountering an earthquake (PGA = 620 gal) in the shaking table test was revealed. The overstrength performance of lateral force-resisting system of the Guangzhou West Tower building's structure was researched, which is caused by the artificially adjusted earthquake influence coefficient of the long-period segment of response spectrum. The response spectrum analysis and the elastic/plastic incremental dynamic time history analysis were conducted to obtain the overstrength coefficient of the lateral force-resisting system that was calculated with the overturning moment at structural base. The analysis results showed that the yield overturning moment at structural base exceeds the seismic demand at the point where PGA = 400 gal, which could verify the reliability of the results of shaking table test. The artificial magnification of the long-period segment of response spectrum and the irrational correlation between the seismic grade and the building's height are important reasons that increase the overstrength capacity of long-period building's structure.