It is very important to reasonably estimate parameters of rockfill in study and analysis of rockfill dams. Back analysis of parameters of rockfill according to in-situ measurement is one kind of new method to effectively estimate the parameters. Metropolis accepting rule of simulated annealing algorithm and system identification are applied to improve genetic algorithm during the processing. Applying this improved genetic algorithm to back analyzing parameters of rockfill
the result shows that the algorithm has advantages of higher accuracy
quick convergence etc.. This method is deserved to be popularized for parameters optimization in this filed.