Research Of Roadway Displacement Back-Analysis Based On Genetic Algorithms

The optimization method is an effective tool in back-analysis of displacements of roadway, choosing the bad iteration method will lead to many problems, such as slow constringent speed, bad stability of solutions, local minimization. The globally optimal solution can't be found out. However, the developing genetic algorithm method in recent years has many good characteristics in optimization, this paper will apply the genetic algorithm method to the research on back-analysis of displacements of roadway. It has successfully solved the extreme problems of multimodal function and multi-variable function on the ground of genetic algorithm theory. A preliminary discussion about running parameters of genetic algorithm which will affect the optimization results was made. This paper puts forward the influence degree index and sensitivity index as the evaluation standards of back-analysis feasibility, studies the feasibility of back-analysis about elastic modulus, poisson rate, cohesion, internal friction angle and initial ground pressure(x, y, xy) in detail. With the combination of genetic algorithm and FLAC numerical software, it also develops the back-analysis of displacement program on the basis of genetic algorithm method, and tests this method with specific elastic-plastic displacement example. The results indicate that the back-analysis of displacements with use of genetic algorithm is a good method worth being popularized...