梨第的柔大而思降高 Duct(波纹管或铜管预埋)（管道） 断 (a) Jack Anchorage(锚具) (b) Grouted after tensioning(用水泥浆填塞)， () 对 图8.7后拉混凝土梁 (a)固定模板，并放入内装钢索的套管，灌入混凝土； (b)混凝土凝固后，以千斤顶在两端对钢索施拉力； ()拿掉模板及千斤顶，并在梁的两端固定钢索
Duct（波纹管或铜管预埋）（管道） Anchorage（锚具） Jack Grouted after tensioning (用水泥浆填塞)
Post-tensioning is generally used on site(现场施工)for members cast in their final place. Tendon profiles of any shape can be used
Post –tensioning is generally used on site（现场施工） for members cast in their final place. Tendon profiles of any shape can be used
o Effectively bonded prestressed beam 效粘结预应力梁) ·Un-bonded prestressed beam(无粘结预 应力梁) 波纹管 水泥浆 (a) 塑料套管 油脂 钢绞线 (b)
l Effectively bonded prestressed beam（有 效粘结预应力梁） l Un-bonded prestressed beam（无粘结预 应力梁）
Out-body prestressed beam(体外预应力)
10.2 Basic behavior of P.C