Study on Usage of Expansive Concrete in Concrete Filled Steel Tube

As a promising green material in civil engineering construction, concrete filled steel tube has attracted an increasing attention. However, there may be vibrating imperfect in the construction progress and concrete shrinkage in the hydration process. Thus the application of concrete filled steel tube is not widely in practical engineering. In order to solve this problem, a method using expansive concrete filled steel pipe to replace the ordinary concrete steel pipe was proposed. Experiment and numerical simulation of FEM were employed to analyze feasibility. The experiment is divided into two parts. Firstly, a comparison between the self-stressing expansive concrete and ordinary concrete shrinkage stress was done, the result shows that the self-stressing in expansion of concrete can offset of the shrinkage stress in ordinary concrete. Secondly, FEA was used to prove the compressive properties of the expansive concrete while working with the steel pipe increased somewhat. Finally the conclusion was drawn that the expansive concrete instead of ordinary concrete in the use of steel tube is feasible.