Rehabilitation of Leaked Concrete Flushing Canal with GRP Pipes in Těšnov – Libebeň

The target of this project was the rehabilitation of a 560 m flushing canals made of 3 m DN 1500 Vianini reinforced concrete pipes. Considerable cracks, joint leakage, sedimentation and deposits under the shafts posed a threat to the conduit and required immediate action. All rehabilitation work on the canal was done from the existing shafts or from the operating pipe shaft. Due to the work in the canal, the inlet and outlet had to be closed and the water had to be pumped out. In the whole section, solid sediments on the bottom of the pipe and the chambers were removed and at the same time deposits under the shafts were cleared out. These materials were characterized as contaminated waste.The rehabilitation of the canal consists of relining the existing Vianini DN 1500 pipes using new GRP pipes. These were 6 m long CC-GRP® Pipes DN 1200, PN 1, SN 10000 including Couplings. The elements were installed successively from the pipe shaft into the whole section. The pipes were supported on both ends and rectifying struts on the clips were used to fix them while concreting was done. HOBAS® CC-GRP Pipes were chosen due to their resistance against sulfuric water, their low weight and their easy handling in the existing Vianini DN 1500 pipeline.