Development of Expansive Concrete Filled Steel Tube with a Flat Bar in Center to Energy Dissipative Braced Frame

采用中心带扁杆的膨胀钢管混凝土作为支撑构件，提高耗能支撑框架支撑结构的力学性能。本文对中心有扁杆的膨胀钢管混凝土进行了试验研究。实验结果和讨论可总结如下：1。提出了钢管屈服时中心扁杆混凝土化学预应力的估算公式。我们展示了混凝土在钢管和钢管中的压缩特性的理想化。在混凝土中加入一定量的新型高性能膨胀外加剂，用于生产这种支撑，所需的体积约为常用膨胀外加剂的一半。通过该支撑的循环压缩和拉伸载荷试验结果表明，该支撑在循环高压缩和高拉伸载荷下具有良好的性能。

The purpose of this study is to improve the mechanical properties of the braces in an energy dissipative braced frame by using the expansive concrete filled steel tube with a flat bar in center as the brace member.We carried out some experiments on the expansive concrete filled steel tube with a flat bar in center. The results and discussions of the experiments may be summarized as follows:1.We proposed the estimation formulae of the chemical pre-stress of the concrete filled steel tube with a flat bar in center at yield of the tube.2.We showed the idealization of the compression characteristics of the concrete in the tube and the steel tube.3.A volume of new high-powered expansive admixture in the concrete for the production of this brace needs about half the volume of the usual expansive admixture.4.From the cyclic compression and tension load test results of this brace, we showed this brace had high performance under a cyclic high-compression and high-tension load.