Optimal Railway Tunnel Construction Scheduling Problem by the PSO Algorithm

In order to solve the optimal boring scheduling in the railway construction, the PSO algorithm is introduced to obtain the optimal construction scheduling results. Firstly, the models on railway construction are mainly composed of Model-1, Model-2, Model-3, Model-4, Model-5, Model-6 and Model-7, while the corresponding mathematical functions are also analyzed in this paper. Secondly, objective functions are closely related to minimize the largest boring time among several tunneling gangs, while each tunnel boring time is closely related to the tunnel length, the boring velocity of tunneling gang and the surrounding rock classification of railway tunnel. Thirdly, the parameters in each particle are also introduced and some main steps on the PSO algorithm is mainly given. Finally, numerical results show that the PSO algorithm can solve the tunnel scheduling problem to reduce the tunnel construction time. Additionally, it is important to discuss the objective fitness, the swarm velocity, the computational time and the obtained result in the whole evolutionary process.