预应力钢结构施加预应力的方法有哪些?
发布时间:2015/9/9 9:21:10 浏览次数:806
1.是弹性变形法,钢材在弹性变形条件下,将组成结构的杆件和板件用焊接或螺栓连成整体。在卸除强制外力后,结构内出现恢复力产生的有益预应力。
2.是钢索张拉法,在结构体系中布置索系,通过千斤顶张拉索端,因而在结构中产生卸载应力而受益。这是国内外应用广泛、技术成熟的一种工艺。但索端须有锚头固定,增大材耗,除需要张力设备等外,还需要加大施工成本。
4.是支座位移法,在连续梁、刚架和其它超静定结构中,人为地强迫支座位移(垂直或水平移位),改变支座设计位置,可调整内力,降低弯矩峰值,减小结构截面面积。这种方法可节省钢索、锚头等附加材耗及张拉工艺,适用于地基基础较好的工程。
1. Is the elastic deformation method, steel under the condition of elastic deformation, the structure of rod parts and plate with welded or bolted together as a whole. After unloading forced external force, the beneficial prestressed structure in restoring force.
2. The wire is rafa, layout of cable system in the structure system, by jack cable end, thus unloading stress in structure and benefit. It is widely used at home and abroad, the mature technology of a kind of process. But must have anchor head fixed line end, increase of material consumption, in addition to the need to tension device thereof, also need to increase the construction cost.
(3) is simple and easy method, by hand for medium and small span steel structure engineering of tension is not big. Rely on tighten nut pull the lever, for example, by positive and negative screw bolt lateral push pull cable tension, etc. This method is simple and practical, easy to promote, be applicable to the lack of large areas of mechanical equipment.
4. Is the bearing displacement method, in continuous beam, rigid frame and other statically indeterminate structure, the artificial force bearing displacement (vertical or horizontal displacement), change the bearing design, internal force can be adjusted, reduce the peak moment, reduce area of the structure. This method can save wire rope, anchor top additional material consumption and tensioning technique, suitable for good engineering foundation.