The Research On Optimization Design Of Mountain Expressway Line Shape Based On Genetic Algorithm

In the demand of "strategic development policy The Belt and Road" and the vast mountain,in the mountain terrain highway routing optimization design has become increasingly hot.Mountain route selection is a multi-objective problem.Environmental factors such as environmental protection,economy and complex natural conditions need to be considered.How to coordinate these influencing factors and quickly and effectively seek the optimal route plan is always a difficult problem for highway designers.Due to the limitation of design method and computation model,traditional highway design method and route design system is difficult to coordinate the relationship among multiple objectives,and there are shortcomings such as expert experience and subjectivity.Based on this,combined with the development of computer technology and mathematical technology,this paper aims to solve the above problems,and further studies the optimization design of Expressway Alignment in mountainous area.This paper analyzed the influence factors of mountainous expressway route selection process,describes the selection principle of Expressway in mountainous terrain in the mountainous area,according to the alignment effect factors and classification of the objective function,introduced the corresponding cost function model,establish the relationship between road alignment elements and cost functions,the overall objective function and optimization the target location of highway alignment optimization.By defining the location of the terminal area of the route area,the route corridor belt of the area is delineated,and the optimization model of line alignment and profile alignment is constructed.On the basis of existing research,introduced the application of global optimization of fast and strong operability of the genetic algorithm,this paper introduces the basic principle of genetic algorithm and its corresponding evolution mechanism,combined with the domestic mountain expressway alignment design expert experience analysis of genetic algorithm in the mountainous area plane line shape optimization,profile optimization and their combination optimization in the process of solving the main information of elements on the plane and vertical section,and on the basis of normative mountain technology index constraints,the establishment of the external penalty function constraints on the processing,to ensure that the new route to meet the relevant technical standards for highway engineering.The express route in the intersection of information using floating-point encoding,through pseudo random mechanism in each plane's intersection curve,at the same time in the intersection to determine the variable slope elevation value,and the layout of the vertical curve,in order to get the plane and vertical alignment,and calculate the value of the objective function and fitness route then,according to the selection operator,the crossover operator and mutation operator in order to get a new genetic operation route.Based on the constructed optimization model and genetic algorithm,combined with practical engineering cases,the program is written on the MATLAB platform to optimize the route selection in mountainous area.And the terrain survey data of practical engineering analysis of discrete process,by the program written by the operation of route alignment information elements,the visual alignment optimization after alignment information elements input latitude in the software,and validates the feasibility of the optimization algorithm and the accuracy of the calculation model and the program the results of the.In conclusion,the validity of the proposed optimization method is verified,which can save some energy and resources for the traditional mountainous route selection,and has a certain reference for it.