Record up-sizing using Static Pipe Bursting technology (from 15 inches to 34 inches)

摘要

This paper describes a successful application of Static Pipe Bursting technology that was used in 2017 to replace anundersized gravity sanitary sewer in the City of Maple Ridge, British Columbia, Canada. A major upsize wasrequired (from 15 inches to 34 inches). Seven critical sections (a total of 2,456 feet) of 15 inches diameter PVCsanitary sewer were operating at capacity. With many developments occurring upstream of those sections, the Cityof Maple Ridge had an immediate need to upsize those sections. The sanitary sewer runs through an environmentalsensitive area (the shore of Kanaka Creek, Metro Vancouver’s Kanaka Creek Park, and a green belt) and the areahas high water table. Open cut replacement was not feasible, therefore pipe bursting technology was chosen.In 2014 a smaller upsize (15 inches to 20 inches) was completed successfully a block away and that gave the City ofMaple Ridge the confidence to further explore the potential for larger pipe upsize. The replacement was split into 7sections/pulls averaging 350 feet each. The existing manholes had to be replaced with larger manholes and, astypical, the entry/exit pits were excavated at the manhole locations, to facilitate removal of existing manholes andconstruction of larger manholes at completion of pipe bursting.The equipment used was Groundoburst 2500G Static Pipe Bursting Rig (287 tons of pull force at 250 bars,maximum pull 315 tons). Maintaining the grade of the pipe was critical and with such a major upsize groundheaving was a concern. The flow was maintained during construction through a temporary 8 inches bypass line.The project was completed successfully with no disturbance to existing utilities.