Development of a Structural Design Methodology for Polymeric Spray Applied Pipe Linings
[Thesis]
Kohankar Kouchesfehani, Zahra
Najafi, Mohammad
The University of Texas at Arlington
2020
326
Ph.D. C.E.
The University of Texas at Arlington
2020
Buried culverts are important components of the highway infrastructure. Most large culverts are built decades ago from corrugated metal or reinforced concrete materials and now have reached their design lives. Trenchless renewal techniques can be utilized to enhance load carrying capacity of the existing deteriorated culverts and provide them a new design life. Spray applied pipe lining (SAPL) is a trenchless renewal methodology to renew damaged pipes and culverts by applying layers of liner on the interior surface of the deteriorated host culvert. The development of practical spray applied pipe linings could be of enormous benefit to the Departments of Transportation. Such linings could be a key strategy in extending service life and managing the future burden expected from the aging culverts and drainage structures. The SAPLs generally fall into two categories of cementitious and polymeric materials. Currently, there is no available standard for structural design of SAPLs. In absence of a standard design methodology, some vendors and contractors currently utilize the cured-in-place pipe (CIPP), ASTM F1216 methodology and others are using various classical analytical structural design equations developed for other purposes. To provide an understanding for development of a design methodology, the first objective of this dissertation was to investigate structural capacity of fully deteriorated invert large circular and arch corrugated metal pipes (CMPs) renewed with polymeric SAPL. The second objective of this dissertation was to compare the load carrying capacities of SAPL renewed circular and arch CMPs. The third objective of this dissertation was to check the applicability of ASTM F1216 CIPP design equation for SAPL method. The forth objective of this dissertation was to develop a design methodology for structural application of polymeric SAPL using for renewal of large diameter (span larger than 36 in.) circular and arch culverts. To conduct this research, before application of SAPL, the inverts of CMP samples were cut to simulate fully deteriorated culverts in service conditions and to maximize the applied static load on the SAPL. The pipe samples were buried under two feet (0.6 m) of soil cover. The performances of SAPL renewed CMPs were compared with a same size invert-cut bare CMP under same testing conditions. The results indicated that dependent on the thickness, application of polymeric SAPL can improve the structural capacity of a fully deteriorated invert CMP culvert up to 80%.