Turning the corner

A UK patent has been awarded to an innovative new cast-in rubber gasket corner joint system designed to reduce the risk of segment cracking during tunnel construction


A UK patent has been awarded to an innovative new cast-in rubber gasket corner joint system designed to reduce the risk of segment cracking during tunnel construction. Developed by VIP Polymers Ltd, the new ‘compliant compressible corner’ ensures delivery of consistent load performance along the entire perimeter of the tunnel segment gasket (TSG). This eliminates the risk of a build-up of pressure at one or more of the gasket’s corners during installation, which could potentially contribute to segment cracking during installation.

Steve Casey, VIP’s Sales and Technical Director, said: “We are delighted that the innovative design and manufacture of our new compressible corner joint, which is used across our entire cast-in gasket range, has been recognised with a UK patent. 11An international patent is also pending. Segment cracking during tunnelling operations is a significant cause for concern for both tunnel designers and tunnelling contractors. It is this concern we directly sought to address when we set out to design this new corner joint.

“Our innovation has been very favourably received within the tunnelling industry, and has already been used in a number of tunnel-building projects, with excellent results. VIP’s design has already been specified for use in future tunnelling projects. Excellent test results we’ve witnessed, through to the positive feedback received from within the tunnelling industry, are testament to the hard work and collaborative effort put in by everyone at VIP.”