Development of the bridge management system for Turkey by introducing a condition rating model based on damage types


Tezin Türü: Doktora

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Mühendislik Bilimleri Bölümü, Türkiye

Tezin Onay Tarihi: 2014

Öğrenci: FARAZ MASOUMI

Danışman: FERHAT AKGÜL

Özet:

The decisions regarding the maintenance, repair and replacement of bridges in developed countries are being made using databases and programs built on scientific and technical knowledge. The computer programs that are developed for this purpose are referred to as Bridge Management Systems (BMS; KYS in Turkish). The main function of a Bridge Management System is to keep the maintenance, repair and replacement costs of bridges at an optimum level throughout the bridge lifetime, to continuously sustain the safety, sufficiency and service quality of bridges, and to determine the maintenance and repair activities for bridges. By using the Bridge Management Systems, it is possible to avoid the accumulation of maintenance and repair needs of a large group of bridges in the future and to prevent the inadequate maintenance and repair actions to reach to a critical level which may endanger the structural strength and safety of the bridges. As part of this study, a Bridge Management System is developed for the General Directorate of Highways of Turkey, which has an extensive planning capability extending from micro to macro level planning. At micro level, tasks include the determination of the condition state of a bridge member by measuring the width of a crack observed in the member, and at macro level tasks include the determination of bridge maintenance, repair and replacement decisions based on optimization and prioritization of hundreds or thousands of bridges based on weighted criteria optimization. The project achieved to generate scientific research and technical knowledge in this field by enhancing it with additional scientific research in light of the criteria that are specific to this country. KYS is designed to have a two-level optimization capability. The first phase of optimization, which is at the level of maintenance and repair activities, is performed based on damage types that the bridge members have and Linear Programming (Dynamic Programming) form of the Markovian Decision Process. The optimization method developed based on damage types is a novel approach on this subject and is used for the first time for KYS in this project. For the second phase of optimization, performed at bridge level (for ranking), Multicriteria Optimization method is used. During the development phase of the KYS, scientific literature in related fields have been reviewed and the concepts developed in this field around the world are integrated into the developed system. During the development of the KYS, a unique element condition rating model is developed as part of this thesis. The unique aspect of the developed condition categorization model for elements is that the condition rating of a bridge member is calculated based on the so-called Maximum Impact Factor (MIF) and Distribution Factor (DF) for each damage type. Maximum Impact Factor takes into account the importance and urgency of the damage while the Distribution Factor shows the effect of the damage on the condition state of the element. Details of the developed model are explained in this thesis. As part of the tools developed, this project established a planning and reporting system that will be used by both the General Directorate and by its Districts. The developed system will enable the General Directorate to monitor the safety and the maintenance costs of the bridges it owns and to be able to provide justifications, supported by scientific and technical data presented in the form of technical and administrative reports, to higher authorities at the time when the budgets are being prepared.