ENGINEERING JOURNAL CHIANG MAI UNIVERSITY

Volume 27, No. 01, Month APRIL, Year 2020, Pages 160 - 172

Service life prediction of pedestrian bridge structures in carbonation environment in nakhonpathom province

Banyut Warinlai and Pitisan Krammart

Abstract Download PDF

This study was an investigation on the carbonation depth of pedestrian bridge structures (PDS) in community area of Nakhonpathom province. Cover thickness of PDS, carbon dioxide (CO2) concentration and relative humidity ( RH) of the environment and carbonation depth of PDS were measured. In this study, the PDS were selected in 3 districts of Nakhonpathom province, namely Kamphaengsaen district, Mueang district and Nakhon Chai Si district. The study results were analyzed the occurrence and the effect on the carbonation depth of PDS. The predict for free service life of PDS in both by Fick"es first law of diffusion equation and durability design of carbonation structure of Department of Public Works and Town & Country Planning were considered. The results indicated that the average of the cover thickness of PDS, the average of the carbonation depth of PDS and the average of the carbonation coefficient of PDS were 49.75-55.73 mm, 19.20-31.40 mm and 4.93-8.39 mm/year0.5 , respectively. Nakhonpathom community area having a high amount of CO2 and RH of the environment was at risk of severe deterioration due to carbonation. Moreover, the rate of carbonation depth of PDS located in Mueang district was higher than that of Kamphaengsaen district and Nakhon Chai Si district, respectively. Finally, the proposed method to Fick"es first law of diffusion equation and durability design of carbonation structure of Department of Public Works and Town & Country Planning can predict and calculate the free service life of the PDS exposed to CO2, the result can be used in the design, planning and maintenance of reinforced concrete structures faced by the carbonation environment as well as preventing damage that will occur in the future.

Keywords

Pedestrian bridge, Reinforced concrete, Carbon dioxide, Carbonation, Service life prediction

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