Prestressing concrete elements using tubular reinforcing members - comprises tensioning by cap at one end, filling e.g. with steel balls and pressurising filling from other end

摘要

The concrete pre-stressing system uses tubular or hollow sectional reinforcing members (1) which are closed at one end e.g. by a screw cap (4a) and contain a filling, e.g. steel balls. The member is subjected to tension by applying pressure to the filling from the other end, e.g. by a cap (4b) screwed on that end to pressurise the filling via an insert (6). - After pouring and setting of the concrete the caps and the filling can be removed for re-use. The tube is pref. provided with an external screw thread over its entire length.