Paper Title
Assessment of Surface Water Quality Distribution to Identify Risky Areas of Reinforced Concrete Structure Deterioration: A Case Study along Saranarai Road (Highway No. 205), Non Thai District, Nakhon Ratchasima, Thailand

Abstract
The aims of this study were to observe, analyze, and classify the surface water quality to identify risky areas of reinforced concrete structure deterioration buildings along Suranarai road (highway No. 205), Non Thai district, Nakhon Ratchasima province, Thailand. Twenty-nine surface water samples were collected from the study area, and temperature, electrical conductivity (EC), resistivity, pH, total dissolved solids (TDS), and salinity were tested by Hanna. Chloride content was analyzed by the titrations method, and ions of Ca2+, Mg2+, K+, Fe2+, and Na+were analyzed by atomic absorption spectroscopy (AAS). From the water quality distribution results, the order of abundance is Na+>Ca2+>Mg2+>K+>Fe2+. The high chloride, sodium, salinity, and TDS concentrations were dominantly represented in the study area (Dan Chak, Non Thai, and Sai-O sub-districts), indicating the brackish water and some saline water. In addition, the correlation tendency of chloride, sodium, salinity, TDS, iron, and pH values will cause risk effects on highly deteriorated reinforced concrete in the study area. These risk areas are represented in the dense community and lowland area in Non Thai sub-district at the Na Wah pond and Khlong Dan River, respectively. In summary, these obtained results can be used to identify the boundary and location for basic information and guidelines for monitoring and solving problems of reinforced concrete structures to prolong service life and increase efficiency in this saline area. Keywords - Chloride, Salinity, Saline Soil, Maha Sarakham Formation, Concrete Corrosion.