一、前言预应力构件以其优良的结构性能在建筑中得到广泛应用,在我国的预制构件中,预应力构件占有很大比重。预应力构件抗力的关键是预应力钢筋(钢丝)在构件中建立起的预压应力。它推迟了拉区混凝土开裂,限制了裂缝的发展,增加了构件的刚度,因而大大地改善了结构性能。因此,张拉应力是预应力构件生产的关键 I. INTRODUCTION Prestressed components have been widely used in buildings due to their excellent structural properties. In China’s prefabricated components, prestressed components occupy a large proportion. The key to the resistance of prestressed components is the prestressing stress established by prestressed steel bars (steel wires) in the components. It delayed the cracking of concrete in the pull zone, restricted the development of cracks, increased the stiffness of the components, and greatly improved the structural performance. Therefore, tensile stress is the key to the production of prestressed components.