Inspection and Assessment of Concrete Bridges in the Eastern Economic Corridor

Abstract

This study focuses on investigating the deterioration of concrete bridge structures within the Eastern Economic Corridor (EEC), covering Chonburi, Rayong, and Chachoengsao provinces. These areas are exposed to critical environmental factors, such as carbonation and reinforcement corrosion, which significantly impact the structural stability and service life of bridges. The primary objective of this research is to assess structural conditions by evaluating carbonation and steel reinforcement corrosion through the application of relevant mathematical models. 

The research methodology involved the collection of data from government agencies, including bridge types and quantities. Subsequently, engineering-based formulas were employed to analyze structural behavior and predict deterioration trends. Three key indices Margin Ratio for Safety, Margin Ratio for Durability, and Deviation Ratio were utilized to systematically assess the structural integrity and durability of the bridges. 

The evaluation results revealed that 86 bridges remain in the Latent Period, prior to the onset of reinforcement corrosion, consisting of 25 Box Beam bridges and 61 Plank Girder bridges, based on the Margin Ratio for Durability criteria. Furthermore, based on the Deviation Ratio assessment, the majority of bridges were categorized into Degree 2, indicating the appearance of surface cracks due to reinforcement corrosion, with 250 Slab Type bridges and 205 Plank Girder bridges falling into this severity level. These findings reflect a progressive trend of structural deterioration, highlighting the urgent need for repair and rehabilitation interventions.

The collected data and analytical results from this study offer a practical guideline for developing preventive maintenance strategies for concrete bridges. Such measures are essential to ensure structural safety, optimize service life extension, and enhance the sustainability of bridge infrastructure management within the region.