Maintenance strategies for Highway’s bridge structures in Bangkok area to reduce carbon dioxide emissions

Abstract

The Bangkok Highway District, Department of Highways (DOH), THAILAND, is responsible for highway bridges, more than two hundred (>200) with a combined length of more than 39,500 meters. Almost 50 percent of these bridges are more than 20 years old. These bridges range in condition from good to damaged. Evaluation is based on the Overall Condition Rating (OCR). Most of the bridges are in the Bangkok Metropolitan area, with high traffic and a maximum traffic of 84,838 vehicles per day. Currently, there is an emphasis on environmental sustainability. Maintenance of these bridges are complex and challenging tasks, requiring thorough assessment and planning. Two categories of bridge maintenance are bridge restoration and preventive maintenance. Bridge restoration is the removal and replacement of damaged components. This type of maintenance is appropriate for bridges with OCR levels 1 (Critical) and 2 (Poor). Fifty-one (51) of these bridges require repair, which generates 1,099,609 kg of carbon dioxide. Bridges with an OCR level of 3 (Fair) are suitable for preventive maintenance or strengthening. Fiber-reinforced material is one of the alternatives. This process does not generate carbon dioxide emissions because it does not involve the use of concrete and reinforced steel materials. There are forty-two (42) such bridges, if reinforcement is not done, it will result in increased structural damage, necessitating bridge restoration and generates 905,560 kg of carbon dioxide. To enhance the sustainability of the bridge and the environment, bridge maintenance should be planned using appropriate techniques based on OCR level and emphasis on preventive maintenance. This will reduce carbon dioxide emissions, which is equivalent to planting 905 new trees.