The Studies Of Non-destructive Identification On Steel Structure Using The Method Of Dynamics

Architecture structure is closely linked with human Being'life, so its quality should not be neglected. The steel structure is often used in wide-span structures with many people or costly equipment in it, so it would be a fatal accident if the structure was destroyed. In recent years, great attention has been paid to the research of damage identification on employing structures. The damage on a structure can bring the changes of physical parameter and the free vibration characteristics, and the damages in different location have a different effect on intrinsic modal. So The occurrence^ location and degree of the damage can be identified in theory, according to the differences of modal parameter between damaged and undamaged structure. In order to reduce the number of nodes to be measured and get rid of the degree of freedoms difficult to measure, the method of dynamical condensing was introduced in this paper. The distinction of remnant energy which is a new parameter concerned with damages is introduced, on the base of remnant energy presented by Huang Fang-lin. This method can not only locate the damage exactly and quickly, but also solve the problem that the integral property is difficult to be gotten, so it fits on the application of engineering. This method was used to diagnose the structural damage in numeral simulation analyses and testing analyses. The resolution of analyses and comparison indicated that this method not only can locate the damage (including stiffness decreasing and mass increasing), but also can locate the new damage without the integral property, so it is possible to be used in the long-time inspecting. According to the former analyses, the application and the problems needed to solve in the steel structure is presented.