重大地震条件下,交通网络具有明显的结构变动性,传统最短路算法生成的疏散路径难以满足其在疏散安全性、可通行性、通行能力约束和应变性的要求.为了解决这一问题,在具有通行能力约束的路径规划(CCRP)算法基础上,考虑了上述有关要求,提出了一种地震疏散路径规划算法.该算法的特色在于:(1)引入惩罚函数以满足应急疏散路径对安全性和可通行性方面的要求;(2)将突发交通拥堵点作为虚拟疏散原点纳入到动态路径规划过程,以增加对突发交通拥堵的快速疏散能力.实证表明,所提出的算法可将疏散交通流分配到危险性较低、可通行性较好的路径上,并满足路径的通行能力约束,而且对突发交通拥堵具有必要的应变能力,能较好地满足地震疏散路径规划的需要.
Owing to structure changeability of the traffic network in the period just after earthquake happening, evacuation routes generated by the traditional shortest path algorithm can hardly satisfy the requirements of safety, passability, capacity constrained and contingency. Based on the Capacity Constrained Route Planner (CCRP), a new algorithm for earthquake evacuation route planning aiming at solving the above problem was proposed. The characteristics of which included the following as- pects: (1) penalty function was introduced to improve traffic safety and passability of evacuation routesl(2) sudden traffic congestion point, as virtual evacuation origin, was brought into dynamic route planning process to quickly solve the unexpected traffic congestion. Experiments show that the proposed algorithm can assign traffic flow into the lower-risk and better-passability routes under the condition of satisfying the capacity constrained, improve the contingency ability for sudden traffic con-gestion,and can meet the needs of evacuation route planning for earthquake.