Experimental Evaluation of Water Supply Pipe Joints against Seismic Ground Deformation: A Four-point Bending Test

Due to permanent ground deformation (PGD) such as earthquakes and liquefaction, water supply pipes and connected joints may experience rotation and deflection through losing its function and complex water contamination. Since the specifications of joints are different in each country, evaluating joints are difficult to manage the functional maintenance of water network system. In this study, two metallic and three non-metallic pipe joints were selected through the joints commonly used in Korea. PGD simulation could be conducted through Four-point bending test which derives the result of deflection angle, moment, and strain value for damaged pipes. Each component showed above M-1 grade which resulted based on the grade of ISO 16134. To compare metallic pipe results, collar joint showed stronger binding force than the mechanical joint, but in deflection angle result mechanical showed higher value. In non-metallic pipe test, since its material contains large flexibility, strain value mainly affected its result. Based on this study, functional evaluation of water supply pipeline regarding the PGD was identified through comparing tendency of each joint characterization. Moreover, these data can be expected to be utilized as the basis of performance evaluation and critical component in piping design.