Why Choose Cement Mortar Lining?
Although cement mortar lining is the oldest and most trusted method of pipeline rehabilitation, it is often classified as a “non-structural” method of rehabilitation. This characterization has caused some to question it as the rehabilitation method of choice.
This page will outline some of the test results, both old and new, that prove that cement mortar lining is structural as well as outline the benefits you can expect from a cement mortar lining project.
Although some specific instances may be more appropriate for alternate rehabilitation methods such as slip lining, the vast majority of the U.S. infrastructure is as structurally sound as when it was installed and would be an ideal candidate for cement mortar lining.
After you review the contents of this page, we would be more than happy to discuss with
your particular situation with you and determine the best pipeline rehabilitation method to fit your needs.
Studies, both old and new, have proven the quality and reliability of a cement mortar lining solution.
The Detroit Pressure Test (1940)
In 1940 the City of Detroit, Michigan, conducted a pressure test on a length of 48” diameter x ½” wall riveted steel pipe. The section to be tested was perforated with numerous holes from 1” to 6 ¼” diameter. Cement mortar lining was then centrifugally applied to the inside of the pipe, the thickness of the lining graduating from ¼” at one end of the pipe to 1” at the other. After an adequate curing period, a prescribed hydraulic testing procedure was followed to determine at what pressures failure might occur in the cement mortar lining. The large hole, 6 ¼” in diameter, blew out at a pressure of 305 psi, with a deflection before rupture of .05 inches. The thickness of the lining at this particular hole was 5/8”.
From this test it is concluded that cement mortar lining is structural and that it provides positive protection against leakage under normal operating pressures.
Global Review of Spray-On Structural Lining Technologies (2010)
In 2010, The Water Research Foundation conducted a study to “examine the structural abilities of spray-on linings.” A brief excerpt from the study is included below. You can view a more complete summary here.
“Compared to other water main rehabilitation techniques, spray-on linings have many attractive features, including:
- Ability for one-day return to service
- Nearly effortless service reconnections
- Minimal community impacts
- Low installation costs.
Less certain are the structural benefits of these linings. This report should remove some of this uncertainty through engineering calculations, manufacturer-sponsored testing, and the testing performed specifically for this project. Undoubtedly, they can span gaps and holes in a deteriorating main leading to less leakage. With less leakage, the pipes will also experience lower rates of external corrosion and less risk of breakage from loss of soil support. This will extend the lives of the mains.”
More Information on Cement Mortar Lining
To learn more about the benefits of cement mortar lining and to see a video of the process in action, we encourage you to view our cement mortar lining service page.
To determine if cement mortar lining right for your application, contact Dewcon at 908-832-5710.