Crossrail TBM sewer pass - closest ever

摘要

Protecting the strategically important Ham sewer in London's east end from one of Crossrail's 7.1 m-diameter tunnelling boring machines (TBMs) earlier this year led to a unique civil engineering project. The 500mm sewer pass by one of two large-diameter TBMs is believed to be the closest ever and led to an innovative response from an alliance of partners. The complex 20-day project (with associated works spread over a number of months) saw a 50m, continuous, duplex stainless steel structural lining jacked into place within the existing 2.06m-diameter sewer and precision-welded to standards normally associated with very high-pressure pipelines.