During the application of cold-rolled and twisted bars,not only should it pledge bars strength and ductility,but also it should fulfill requirements of bars standard thickness and panel length.

The pulling and extracting tests of the cold-rolled and twisted bars and experiments on these bars members have all proved that these bars possess comparatively superior ductility and bondability.

Advantages and application of cold-rolled-twisted bar;

The manufacturing technology, stress conditions, construction rules and reinforcement calculation of the laminated floor slabs with cold-rolled-twisted bar are investigated in this paper.

Study on several question existed in tensile test of cold-rolled and twisted bars;

It can make construction quick and convenient,and can save the quantity of bars 42 percent that cold-rolled and twisted bars instead of grade Ⅰ bars used in concrete slab.

The features of cold rolled twisted bar are introduced as well as its application scope and situations.

The paper states technique of in-situ concrete continuous slab of cold rolled twisted bar rein forcement.

In this paper the relationships among deformation rate, temperature and plasticity of cold rolled and twisted bars are discussed, and also the equation for deformation rate of cold rolled and twisted bars is derived.

By means of the experiment on the concrete slabs with cold rolled and twisted bars, the general situation of cold rolled and twisted bars is introduced in this thesis.