铁路混凝土工程钢筋机械连接的设计及加工工艺控制

Design and construction technology control of mechanical connection of steel bars in railway concrete engineering

目前铁路混凝土工程大量采用钢筋机械连接,取代了传统的钢筋焊接连接方式。本文依据"等强度连接"设计原则,选取铁路混凝土工程常用的ф16,ф25,ф32钢筋分别代表小、中等及大直径钢筋,采用不同的螺纹间距,开展了钢筋机械连接套筒的优化设计,得出了钢筋机械连接套筒螺纹规格及相应的尺寸,并进行了钢筋机械连接试验组件的加工工艺研究。此外,对连接组件加工过程的常见工艺缺陷给出了处理对策,这对钢筋机械连接的现场应用具有一定的指导意义。静力拉伸、高应力反复拉压、大变形反复拉压试验结果表明,该组连接接头的强度和变形性能均满足等强度连接的要求,可以用于螺纹规格优选及下阶段的疲劳性能试验研究。

Mechanical connection of bars which has replaced conventional welded connection is extensively applied in railway concrete engineering. Based on ＂equal-strength connection ＂ principle,the optimization design of bar mechanical connection was carried out,and commonly used ф16,ф25 and ф32 bar diameters were selected to represent small,medium and large diam eter bars. Thread size and corresponding mechanical connection dim ensions were obtained. Construction technical control of mechanical connection of bars was researched and treatment measures of common technological flaws were provided. It should be of great guiding significance to in-situ application. Results of static tensile tests,repeated tensile and compressional tests at high stress level or at large deformational condition proved that static strength and deformation performance of mechanical connection were qualified with codes,and should be used for further thread size optimization and fatigue performance tests.