中文摘要：

现有的对施工区最优长度的研究,在考虑交通分流时都是在假设绕行道路的通行能力足以承受绕行交通量和绕行道路上已有的交通量的前提下,没有考虑到绕行道路上是否会发生排队。针对绕行道路可能发生排队的情况,研究该情况下的施工区长度和施工总成本的关系,建立以施工区长度为自变量的施工区总成本模型。根据主道路和绕行道路是否发生排队,将总成本模型分为四种形式。研究的目标是总成本最低,采用一定的方法推导出不同情况下的施工区最优长度计算公式和最佳的分流比例。算例研究表明,该模型能够有效地优化不同情况下道路施工工程的施工区长度;当主道路上到达的交通量较大时,适当的分流比例能有效地降低总成本。

英文摘要：

The present research on the work zone length optimization is all under the premise that the detour capacity is large enough to support the traffic volume, including the diverted traffic and the existing traffic on the detour. Whether it neglected the detour will have queues. To study the relationship of work zone length and work zone total cost under this situation, this paper established a work zone total cost model in terms of a variable ： the length of the work zone segment. According to whether the main road or the detour would have a queue, the model had four forms. The goal was to minimize the total cost. Then it presented a methodology to calculate the optimized work zone length and the proper diversion ratio. Finally, through a numerical example, it shows that this model can optimize the work zone length under different circumstances. When the approaching traffic flow on main road is large, proper detour plan can decrease the total cost.