Structural Evaluation of Polymeric Spray Applied Pipe Lining through Full-Scale Soil Box Testing

Spray Applied Pipe Lining (SAPL) is a trenchless technology method that is used by Departments of Transportation (DOTs) and City, State and Federal entities to structurally renew deteriorated gravity storm conduits and culverts. In comparison with other renewal methods, SAPL provides more flexible installation, specifically in limited access conditions, and faster completions, resulting in lower costs. The SAPL method applies layers of liner on the interior surface of the host pipe to provide corrosion protection and structural capacity enhancement. This paper presents the results of three full-scale laboratory tests, evaluating the structural capacity of fully deteriorated 60-inch corrugated metal pipe (CMP). To simulate a fully deteriorated CMP, the inverts of the pipes were entirely cut and the crown of the pipes were deformed, then buried under two feet of poorly graded sand and renewed using structural polyurea with the thicknesses of 0.5, 0.65 and 2.5 inches. The soil-pipe systems were then loaded using a 330-kip hydraulic actuator. The test results show, in the absence of pavement, that implementation of polymeric SAPL can increase the load carrying capacity of the fully deteriorated CMP up to three times higher than the required AASHTO H20 truck service load.