Formulation of Long-Term Sustainable Bridge Maintenance Plan for the Department of Rural Roads Bridges in Thailand

The Department of Rural Roads under the Ministry of Transport of Thailand currently maintains about 7,000 bridges in the Kingdom. Prior to the development of a long-term maintenance plan, the department adopted a responsive maintenance approach where repairs works were carried out when serious defects or damages were detected. Such ad-hoc approach may increase the life-cycle cost and may reduce the bridge safety and reliability. With the number of bridges growing and with limited budget and manpower, it was clear such approach could not be sustained in the long run. Through cooperation with Japan International Cooperation Agency, an effort was initiated in 2010 to develop a long-term, efficient and cost-effective preventive bridge maintenance plan. Due to their high importance, twelve major bridges crossing over Chao Phraya River were selected as reference bridges in the formulation of the long-term bridge maintenance plan and is discussed in this paper.