OPTIMIZATION INVERSION OF THE PRESENT GROUND STRESS FIELD OF BOHAI SEA BASED ON HOOKE-JEEVES ALGORITHM

An optimization inversion model of 3D ground stress field of the Bohai Sea was established based on the in-situ stress data from the existing measuring points in the study area and the analyses of tectonic evolution background and characteristics of Bohai Sea. By comparing the stress values and directions obtained at measuring points by means of finite element method with the in-situ measured data, an error function was established and taken as the optimization object function. The optimization inversion analysis was carried out by combining the Hooke-Jeeves optimization algorithm and the finite element method. The optimization inversion calculation process was completed by taking the finite element analysis program ANSYS as a calculation module and calling circularly the batch model through the Matlab platform, thus obtaining the distribution law of the present shallow ground stress field in Bohai Sea. The research results have shown that the method presented in the paper can be used to inverse a more reasonable stress field distribution by using the data from less measuring points, thus offering a reference for further study of the tectonic activity in Bohai Sea.