Optimization of Repair and Recover of Infrastructure Systems Considering Life-Cycle Cost

到去年为止，已对寿命周期成本的定义及其在基础设施系统维修方面的应用进行了研究。尝试开发一个最佳的维护系统使用寿命周期成本的概念。在此基础上，对系统进行了改进，并利用真实的数据验证了系统的实用性。为了应对老化和环境的各种不确定性，引入了可靠性理论。今年，我们打算完成系统，并为我们提供一个可靠且功能充分的实用维护计划。为了处理不确定性，开发了一种新的系统，它没有明确使用概率论。由于概率方法往往难以理解的从业者，该系统采用了一种新的优化方法来处理的不确定性。应用Tamaki等人提出的遗传算法，可以在不使用概率概念的情况下引入关于环境条件的恶化和变化的预测的不确定因素的影响。另一方面，开发了另一种系统，该系统可以为大型复杂结构的维护问题提供实用的解决方案。利用基于病毒进化概念的遗传算法，可以得到结构中单个元件或构件的维修计划以及整个结构的总维修计划。该系统可以减少计算时间和内存。通过研究，得出了用户成本的计算对于合理估算寿命周期成本的重要性。因此，非常重视用户成本的定义和计算，并证明了他们的有效性，将其应用于北海道的道路网络。

Up to the last year, research had been made on the definition of life-cycle cost and its application to the maintenance of infrastructure systems. An attempt was made to develop an optimal maintenance system using the concept of life-cycle cost. Furthermore, the system was improved for practical use and its applicability was demonstrated using the real data. Then, the reliability theory was introduced so as to deal with various uncertainties regarding the deterioration and environments.This year, it was intended to complete the system and provide us a practical maintenance plan which is reliable and sufficient for functionality. In order to handle the uncertainties, a new system was developed, which does not explicitly use the probability theory. Since the probabilistic method is often difficult for practitioners to understand, the system employed a new optimization method to deal with the uncertainties. Applying the genetic algorithm proposed by Tamaki et at., it is possible to introduce the effects of uncertain factors with respect to the prediction of deterioration and the change of environmental conditions without using the probability concepts. On the other hand, another system was developed, which can provide a practical solution for maintenance problems of large and complicated structures. Using the genetic algorithm based upon the concept of virus evolution, it can be done to obtain each maintenance plan for individual elements or members of a structure as well as the total maintenance plan for overall structure. This system can reduce the computation time and memory. Through the research, it is concluded that the calculation of user cost is quite important to estimate the life-cycle cost appropriately. Therefore, great attention was paid to the definition and calculation of user cost and their validity was proved by applying them to a road network in Hokkaido.