gh tavakoli mehrjardi - Department of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran
s.n moghaddas tafreshi - Department of Civil Engineering, K. N. Toosi University of Technology, Tehran, Iran
a.r dawson - Nottingham Transportation Engineering Center, University of Nottingham, Nottingham, UK

Traffic loading can produce a semi shock on the trench involved with pipe and tent to damage the lifelines buried in the soil and also permanent settlements may happen. This study describes the construction and testing of 13 trenches containing buried uPVC pipes as typically installedbeneath roads for drainage purposes. Each trench was backfilled and subjected to repeated plate loading test with the intention of approximately replicating the trafficking. Both surface settlement of the trench top and deflection of the pipe at the trench base were monitored. Many of the installations were reinforced at the top with a geosynthetic reinforcement to evaluate their potential in limiting deflection of the trench surface and of limiting the compression of the pipe in the trench. The investigation provides graphical output from the experiments and concludes that the more rigid sheet geosynthetic used had the greatest potential to provide surface reinforcement. The planar geosynthetic was the best material tested as far as surface settlementwas considered. However, its ability to protect the pipe from straining wasn’t so well developed under repeated loading, even though it worked well under initial loading. Cellular reinforcing geosynthetic also had potential but it was more demanding as regards compaction installation.

Buried Pipe, Settlement, Plate Loading Test, Repeated Loading, Geosynthetic