New Pipeline Construction Product Allows for Simple Installation of Standard PVC Pipe in Houston HDD Project

By Dennis Shumard, P.E., MASCE, and Pat Moravits, BRH-Garver Construction | March 2014, Vol. 69 No. 3

Most of the application involved straight runs of pipe. However a portion of the eight-inch line was required to negotiate a slight curve to parallel the street. A portion of the project drawing showing the curved section is shown in Figure 6.

Figure 6: Portion of project plans showing the curved trenchless installation requirement.
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This was achieved utilizing standard drilling and bit location techniques. Once the bore was completed the pipe was pushed in as before and the piping easily followed the established curve. The ERS component of the Mega-Stop device is important to allow for and to be able to maintain the flexibility of the pipe joints needed to navigate the curve.

Figure 7: Inspection camera
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As a means of demonstrating the effectiveness of the mega-Stop assembly, a video inspection was performed on a portion of the eight-inch section of the pipeline to verify that the pipe joints were properly assembled and not over-inserted. The camera, shown in Figure 7, was inserted in the pipe at an open location where a fitting was to be installed. Over 300 feet of installed piping was inspected and every one of the joints was found to be installed properly. A screen shot of the inspection video can be seen below in Figure 8.

Figure 8: Screen shot from inspection video showing proper gap in the pipe joint.
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Conclusion (subhed)

Aging infrastructure is an issue that any water and/or wastewater utility must deal with on an ever increasing frequency as pipelines start to fail or must be upgraded to meet new demand requirements. The use of trenchless installation techniques for replacing these lines is becoming more and more prevalent and minimizes the damage and disruption to adjacent property and utilities.

Frequently, this type of installation also requires limited excavation and entry and numerous fittings. Use of the Mega-Stop bell protection device with standard AWWA C900 and C905 PVC pipe simplifies material acquisition and allows for the close quarters and frequent fitting connections required in these applications.