- ENGINEERING INFO
- CASE STUDIES
With annual average daily traffic (AADT) of nearly 70,000 vehicles, the section of I-35/I-70 that passes through downtown Kansas City, Missouri is one of the most highly traveled roads in the greater metropolitan area. When Kansas City Water Services Department (KCWSD) decided to replace a failed 16-inch cast iron water line under the interstate that predated its construction, it was clear that traditional open-cut construction was not an option.
Based on the need to perform significant utility relocations in advance of the Kansas City Street Car Project, KCWSD determined it was an appropriate time to address the failed 16-inch line. Kansas City-based engineering firm, Burns & McDonnell, was under contract to design the water and sewer utility relocations required by the Kansas City Streetcar Project in the downtown area.
Initially, Burns & McDonnell evaluated installation of a new 16-inch water line inside a steel casing in close proximity to the existing line. The required space for the jacking pits necessary to install a steel casing via jack-and-bore would have been difficult and costly. Installing a Fusible PVC® carrier pipe within a directionally drilled Fusible PVC® casing was determined to be feasible. After further review of the water model for the area, however, it was determined that the full 16-inch line capacity was not required. A 12-inch water line could provide adequate flow to meet the looping requirements.
At that point, the most economical solution became clear. Burns & McDonnell recommended sliplining the existing 16-inch cast iron line with a 12-inch Fusible PVC® carrier pipe. Jeff Heidrick, Project Manager for Burns & McDonnell, stated: “Fusible PVC® pipe provided the largest inside diameter of any fully structural rehabilitation option that would fit within the existing 16-inch line. Based on our previous experience with Fusible PVC® pipe, we were confident this would be an excellent long-term solution.”
|Pipeline Details and Project Summary|
|Project:||Street Car Slipline Project|
|Location:||Kansas City, Missouri|
|Pipe Size:||12” DR18 Fusible C-900®|
|Pressure Test:||200 psi|
|Owner:||Kansas City Water Services|
|Engineer:||Burns & McDonnell; Kansas City, Missouri|
|Contractor:||Redford Construction; Raymore, Missouri|
Redford Construction of Pleasant Hill, Missouri was selected as the contractor for the Street Car Water System Replacement Project, which included the slipline scope of work. The existing 16-inch line was cleaned and televised prior to installation. During installation, a slight offset was discovered in the line that eliminated the use of casing spacers. With no bells or collars, Fusible PVC® pipe did not require casing spacers because the fused joint is the same dimension as the barrel of the pipe, allowing the pipe to rest on the bottom of the casing without creating stress concentrations or producing excessive deflection.
Although work conditions were tight, installation proceeded smoothly even with the need to fuse on two additional sticks of pipe during pull-in due to the lack of available laydown space to pre-fuse the entire pipe string prior to installation. Thomas Hudgens of Redford Construction stated, “The entire process went extremely well and we look forward to working with Underground Solutions on future projects.”