After the tensioning operation, the space between the tendons and the ducts are _______

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

The Hoyer’s method of prestressing is done by _______

The chemical pre stressing is generally suited for elements like _______

Which is one of the systems used for pretensioning?

When the concrete attains sufficient strength, which elements are released?

The method of tensioning Magnel-Balton system involves _______

The linear expansion of the cement in chemical pre stressing is about _______