Research Of Road Quakeproof Option Based Onexpected Rescue Time

Slow rescue caused by road network damage after earthquakes is the main reason for huge earthquake casualties. On one hand the reason for road network damage is the high destructive of earthquakes, on the other hand is the lack of road earthquake-resistant design. And there are two ways of improving road network’s ability to accelerate the speed of rescue: preventive reinforcement pre-earthquake and emergency repair post-earthquake. In contrast, preventive reinforcement pre-earthquake not only has lower economic costs, but also has greater reduction in rescue time. However, the difficulty of preventive reinforcement pre-earthquake lies in determining which sections of reinforcement will have the minimum road network rescue time after earthquakes.This paper focuses on the difficulty of preventive reinforcement pre-earthquake, that is to determine a set of sections of the road network under certain investment constraints, and result in the minimum road network rescue time after earthquakes.Firstly, the concept of expected section rescue time is proposed from the viewpoint of probability to make quantitative research of rescue time in uncertain road network post-earthquake, and parameters such as section seismic reliability are assigned. Then, we get the expected section rescue time model under investment variables, and set out minimum expected road network rescue time through two types of shortest path and section weights.Secondly, taking minimum expected rescue time based on shortest path as objective function, and combining the research of seeking all paths in OD, we build section reinforcement selection model which considers shortest path in the network which have only one OD, and promote the model to multiple OD network. There is no better algorithm for solving this complex quadratic integer programming model by analyzing objective function and constraints. Through analysis of intuitive of the objective function, the verified formulas of minimum road network expected rescue time are achieved.Then, taking minimum expected rescue time based on section weights as objective function, section reinforcement selection model which considers section weights is established combining the research on section weights’calculation. And according to three special road networks of the shortest path is not unique, section weights are zero, and different OD has different importance, we correct parameters’ calculation method in this model. Through the structural analysis of objective function and constraints, the model is converted to a0-1knapsack problem, and dynamic planning algorithm to solve the knapsack problem is illustrated.At last, according to the effect of Wenchuan earthquake on Longmen Mountain fault zone, Dayi is in the high seismic zone, and we build a virtual7.5-magnitude earthquake in Dayi. On the basis of parameter calculation, mathematical model and algorithm in front text, we put the actual problem into a mathematical problem, and find out the sections which can get minimum expected road network rescue time. We use verified formulas of minimum expected road network rescue time to examine the results, which verifies the rationality and effectiveness of the theories, mathematical models and algorithms in this paper.