On the basis of a hierarchical genetic algorithm(HGA) and the idea of structural optimization

a method for multiple damages detection of an Euler-Bernoulli beam and a 2-D plate structure was presented.The algorithm employed control genes to represent the number and location of multiple damages and parametric genes to denote damage extents

effectively avoiding the premature phenomenon of conventional genetic algorithm(CGA).The results of a cantilever beam and a 2-D cantilever plate simulation examples show that the good agreements with the actual situation can be obtained by using the present method

but CGA can't accurately predict multiple damages of the plate.For the simulation of the cantilever beam

the average values of depth prediction errors for HGA and CGA are 0.144% and 1.819%

respectively. The iteration numbers of finite element computation of HGA are only 16.4% of that of CGA.Compared with CGA

HGA remarkably improves the computational efficiency

accuracy and stability.