Bridge Drainage Pipeline in Zagreb
The complete pipeline consists of three major sections. MCP Culinecka is the first running from the treatment plant to the so-called Homeland Bridge. This part was accomplished by open cut installation with well compacted gravel sized 0 – 16 mm. The utilized HOBAS Manholes are T-Pieces DN 1000/800 covered with stainless steel blank flanges. Flexibility regarding maintenance or repair works is given with mechanical couplings that join the manholes to the pipeline so that they can be easily disconnected and taken out of their concrete housing any time if necessary. The second section is the 900 m long Homeland Bridge that carries a road and tramway and furthermore holds 5 parallel pipelines DN 1000 inside the construction. Four of the pipelines are for potable water and one is a HOBAS CC-GRP Sewer Main for New Zagreb’s wastewater. The 1 km long HOBAS SewerLine® is installed on stainless steel supports with 5.85 m clearance. Since the only fixed point lies in the center of the bridge, thermal dilatations are carried out to both sides with the bridge moving up to 50 cm. KRESTA compensators are utilized here to absorb these movements – a demanding task considering the relatively large diameter, the pressure and line movement.