The basic chemical substance used for pre stressing forces in concrete member is _______

The period of cooling in thermo electric pre stressing is observed as _______

The drawback of Lee-McCall system is it cannot use _______

The Freyssinet system of post tensioning anchorages was developed in _______

The transfer of prestress of concrete is achieved by _______

The chemical pre stressing is also called as _______

The thermo electric pre stressing is also used in _______

In Lee-McCall system, the prestressing tendons are in the form of _______