A flexibility matrix-based damage locating technique was used to find the most possible damaged elements of the structure,and then the damage severity was estimated using the second order eigen-sensitivity analysis method.

The mass-normalized mode shapes were obtained from the eigen-sensitivity analysis.

This approach is comprised of the damage locating vectors method and eigensensitivity analysis.

In this paper, a second order direct perturbation method for eigensensitivity analysis of arbitrary nondefective system is developed.

The grain size characteristics and the fluctuation of lake surface of the core in Holocene in Dabusu lake;

Based on the analysis of the grain size characteristics of the sediment in Nanhui joinit area between Changjiang and Hangzhou bay,the net transport trends in Nanhui area are studied by using "Gao and Collins" model.

The enclosed Lake Daihai lies in the environment sensitive zone in North China,and the grain size characteristics of its sediments indicate the variations of precipitation,hydrodynamics and the lake level changes.

After the working on the Yangtze River,Yellow River, Haihe River and Huaihe River for palaeoflood, a mark system of characteristics of grain size for palaeoflood slackwater deposits is first time given in this paper, which has wide use in palaeoflood study.