Search:

Trenchless technologies solve problems in Sofia

The application of a trenchless technology became the solution for a problematic pipeline in the area of TV Tower in the capital.

The application of a trenchless technology became the solution for a problematic pipeline in the area of TV Tower in the capital. That was a water-main consisting of two parallel steel pipes, Ø 920 mm, passing perpendicularly under Peyo Yavorov Boulevard.  The bad condition of the water facility, which was built over 60 years ago, lead to a number of failures, and its recent conventional open-cut repairs caused road collapse and endagered the life of the people on the boulevard. The boulevard has extremely busy traffic and it is still in its warranty period after its major repair so the rehabilitation of the main pipeline using an open-cut technology was impossible. The possibility to rehabilitate the pipes without disturbing the traffic was offered by Stroitelna Mehanizatsia AD. They applied the Cured-in-place Pipe Technology which involves inserting a liner soaked in epoxy resin into the old facility. The liner firmly sticks to the walls of the pipe and after the curing of the resin, a new pipe is formed inside the old one.  Because of the big diameter and length of the pipes, the project was realized with an inversion vessel produced by the company, which was big enough for the necessary liner and resin. The rehabilitation was implemented within a twenty-four hour period for each of the pipes. In this way 100% of their integrity was restored and their life-time was extended with over 50 years.