Quick Culvert Repair

This article describes what happens when culvert failure occurs and discusses the options for replacement. As corrugated metal pipe (CMP) deteriorates, the protective galvanized coating corrodes, leaving the steel pipe which rusts away over time. This commonly occurs at the pipe invert. As the invert deteriorates, the surrounding soil pressure forces the pipe to turn inward at the invert and close up or buckle. These conditions negatively impact the pipe bedding material, which loses structural integrity as it erodes under the damaged invert and around the damaged pipe. Open-cut replacement of a culvert is an option, but more often, trenchless methods such as lining, sliplining, or standard tunneling methods are used to replace or rehabilitate the deteriorating line. A case study is highlighted in which a deteriorating culvert was replaced using a tunneling method. An existing 48-inch-diameter culvert carried a stream under a highway in northern Delaware. The culvert’s invert was rusting through and the seams had opened up to the extent that bedding material was beginning to migrate into the pipe. The existing CMP was replaced with new 54-inch-diameter reinforced concrete pipe, using tunneling instead of open-cut as originally specified in the contract. The cost savings to the state was approximately 30% of the original contract amount. The new pipe was installed under each side of the highway from a single pit in the median. A jacking unit pushed reinforced concrete pipe through the tunnel as workers removed the old pipe and excavated the face. In approximately 15 working days, the new concrete pipe was in place. This case study demonstrates how tunneling with long design life products can be a cost-efficient way to rehabilitate or replace deteriorating culverts under roads.

Language

  • English

Media Info

  • Media Type: Print
  • Features: Photos;
  • Pagination: pp 42-44
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01142482
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Oct 26 2009 1:23PM