Research Of Construction About Self-stress Concrete-filled Steel Tube(scfst)arch Bridge

Whether the concrete filled steel tube(CFST) can give full play to the role of the two materials,and the core concrete fully,uniformly and compactly filled steel pipe,all of these will affect the mechanical properties of CFST, thereby affecting the whole structure of the bearing capacity and safety.Self-stressing concrete filled steel tube(SCFST) forming a new steel--concrete composite material use the high performance expansive concrete to instead of the ordinary concrete. SCFST which conbine the self-stress, expansion and the constraint of steel tube have solved the above problem. SCFST fully tap the potential of CFST'bearing and is the development and improvement of CFST.How to ensure the core concrete's construction quality has some difficulties in concrete mix design and construction. Through high performance expansive concrete in the steel arch bridge in the applied research,this article resolved steel and concrete problems of void. The main contents of this paper include:â‘ By researching on mix design of self-stressing concrete filled steel tube,it can solve the problem caused by improper mix design,which led to severe shrinkage of concrete or discontinuity,uneven, and so on void of concrete;â‘¡Researching on the pumping placing construction method, we can solve the problem of void result from improper construction methods of concrete Pipe,and amend current menthod;â‘¢Apply the results of these two studies to New Dragon Gate Bridge in Chongqing Wushan, and improve their correctness by the results of the actual project;â‘£Compared technical and econmical aspects of self-stressing concrete filled steel tube with that of ordinary concrete filled steel tube, we can improve self-stressing concrete filled steel tube is more reasonable than ordinary concrete filled steel tube because of exist of self-stressing.