Joint response of existing pipe culverts under surface live loads

This study investigates the field performance of culvert joints in five existing pipe culverts. Test culverts consisted of two corrugated metal culverts, two reinforced concrete culverts, and one high-density polyethylene culvert. Culverts were selected for backfill depths less than 1.5 m and inner diameters ranging from 0.9 to 2.1 m. Static loading was applied to the culverts by parking a heavily loaded truck at different positions above the culvert joint. Dynamic loading was applied by driving the truck over the culvert at speeds ranging from 8 to 48  km/h. Culvert deflections and strains were measured near one of the culvert’s joints. Separation at the joint was also measured. The results indicate that separation at the joint was quite significant at times. In the worst case, the measured separation at the joint was equal to 50% of the measured deflection. Strains measured near the joint in steel culverts were significantly smaller than the yield strain. The dynamic deflections were typically 10–40% less than the static deflections.