Trench TechnologyThe trench technology requires excavation, removal of existing pipe, placement of new pipe, and compaction of backfill. These actions cause longer disruption to traffic (compared to trenchless methods) and may require more funding. To improve long-term performance and sustainability of buried pipes, steel-reinforced high-density polyethylene (SRHDPE) pipes have been used increasingly to replace concrete and steel pipes. SRHDPE pipe uses steel ribs to carry loads and a plastic cover to protect steel ribs from possible corrosion during its design life.

Trenchless Technology Trenchless rehabilitation methods have been used increasingly to reduce overall project cost and disruption of service as compared

Technologies for Replacing and Rehabilitating Corroded Steel Drainage Pipes in Roadways

By Jie Han, Ph.D., PE, F.ASCE, Glenn L. Parker Professor of Geotechnical Engineering

University of Kansas School of Engineering Department of Civil, Environmental, and Architectural Engineering

Since the National Interstate and Defense Highways Act was implemented by President Eisenhower in 1956, many

drainage pipes including steel pipes have been placed inside or across highways. Some of these steel pipes are going to reach the end of their service life due to extensive corrosion. Figure 1 shows two badly-corroded steel pipes across two roadways in Kansas. These corroded pipes are vulnerable to crushing due to surface loading if shallowly buried; therefore, they should be replaced or rehabilitated.

IntroductionThis article discusses the technologies available for replacing or rehabilitating corroded or damaged pipes in roadways, which can be classified as trench and trenchless technologies.

Figure 1. Corroded Steel Pipes (a) Pipe buried in roadway (b) Pipe exhumed from roadway

LTAP Fact SheetKansas

Spring 2009

A Service of The University of Kansas Transportation Center for Road, Street & Bridge Agencies

Kansas LTAP Fact Sheet 2019 Page 1

with the trench method. Sliplining is the most common trenchless rehabilitation method used for rehabilitating corroded steel pipes. With sliplining, a new pipe liner of smaller diameter is placed inside an existing corroded pipe and grout is used to fill the space between them. Commonly-used liners are plastic pipes made of high-density polyethylene (HDPE) or polyvinyl chloride (PVC). In general, sliplining can improve the structural and drainage capacity of corroded steel pipes.

Research Conducted to Test Performance Since 2011, graduate students in the Geotechnical Engineering and Materials Group at the University of Kansas, led by Prof. Jie Han and Robert L. Parsons as principal investigators, have worked on three research projects sponsored by the Kansas Department of Transportation (KDOT) to investigate the performance of SRHDPE pipes and the sliplining technology. Through careful and

comprehensive small-scale laboratory testing, large-scale box testing, field installation and monitoring, and numerical analysis, the research team verified the performance of these two technologies for replacing or rehabilitating corroded steel pipes buried in roadways. Figure 2 shows the installation of SRHDPE pipes and the HDPE liners in two Douglas County Public Works projects close to Lawrence, Kansas. Figure 3 shows the completion of these two projects.

SummaryIn addition to traffic loading tests right after the installation, the research team monitored the deformations of the SRHDPE pipes placed in service for two years, demonstrating their satisfactory performance. The research team also conducted plate-loading tests on the pavement with the HDPE sliplined corroded pipe, showing increased load capacities and stiffness of the pavement and the pipe.

Figure 2. Installation of SRHDPE Pipes or HDPE Liners(a) Replaced with SRHDPE pipe (b) Sliplined with HDPE liner

Figure 3. Newly-installed SRHDPE Pipe and HDPE Sliplined Steel Pipe (a) Newly-installed SRHDPE pipe (b) HDPE sliplined steel pipe

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References Details about the above research work can be found in the following references:1. Han, J., Rahmaninezhad, S.M., Al-Naddaf, M., Parsons, R.L., Jawad, S., and Liu, H. (2019). Grouting Effects on Performance of Sliplined Steel Pipes. Report Number: KU-17-3 (KDOT Project No. RE-0716-01)2. Wang, F., Han, J., Khatri, D.K., Parsons, R.L., and Corey, R. (2019). “Time-dependent field performance of steel-reinforced high-density polyethylene pipes in soil.” Journal of Geotechnical and Geoenvironmental Engineer-ing, ASCE, in press.3. Khatri, D.K., Han, J., Corey, R., and Parsons, R.L. (2013). Establishing a Design Procedure for Buried Steel-Rein-forced High Density Polyethylene (SRHDPE) Pipes, Final Report, KDOT, K-TRAN: KU-11-6.4. Han, J., Wang, F., Khatri, D.K., and Parsons, R.L. (2015). Establishing A Design Procedure for Buried Steel-Rein-forced HDPE Plastic Pipes – A Field Study (Phase II). Final Report, KDOT, K-TRAN: KU-14-4.

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