Wastewater project with sulphate-resistant steel fiber-reinforced concrete segments
The 100,000 tunnel segments used for the main sewer line of the STEP project in Abu Dhabi are exposed to attacks of heat and high chloride and sulphate contents of the surrounding ground. A specially adjusted steel fiber-reinforced concrete mix is to withstand the aggressive boundary conditions.
The wastewater project (Strategic Tunnel Enhancement Program, STEP) of the ultramodern capital city of the United Arab Emirates, Abu Dhabi, gives an idea of the severe conditions, imposed on the durability of concrete, other regions are faced with. The tunnel segments of the miles long main sewer lines, which are driven by means of tunnel boring machines, are installed in an aggressive and hot environment: the fresh concrete may begin to boil there, when hardening, and extreme chloride concentrations are corroding concrete components in just few years. Neither conventional reinforcement nor...
