Centrifuge testing to simulate buried reinforced concrete pipe joints subjected to traffic loading

Pipeline water leakage has become a serious problem in many countries. It has been widely noted that most of the damage to the pipelines occurs in the joints where two pipes are connected to each other. This paper presents the results of a geotechnical centrifuge testing program in which the response of a 12 m long (in prototype scale) large-diameter reinforced concrete pipeline with gasketed bell-and-spigot joints subjected to three standard American Association of State Highway and Transportation Officials design load configurations has been investigated. The results show that most vertical pipe movements occurred during the first 10 cycles of traffic loading. Under design tandem loading, the pipe joint displacements were significantly higher than those under the other two traffic load configurations. An increase of soil cover depth resulted in a reduced influence of surface loading, the effect of which was the most significant for two single pairs of wheels of design trucks in passing mode. Furthermore, two pipes on the left side and two pipes on the right side from the tested joint were influenced significantly by the surface loading, while the pipeline movements were not symmetrical. Although the joint directly under the load experienced the largest rotation, the possibility of leakage in the second joint in the spigot-to-bell direction was also high, due to large differential displacement between the pipes.