Study Of Cavity And Self-stressing Detection Technology For Self-stressing Concrete Filled Steel Tubular Arch Bridge

Concrete-Filled Steel Tube structure has been widely used in high-rise buildings and long span arch bridges. However,there are commonly void problems in ordinary Concrete-Filled Steel Tube structures,which constrained its advantages seriously. The self-stress that through the expansion of high performance expansive concrete to produce can solve the problem of Concrete-Filled Steel Tube void. However, how to test the Self-stress Concrete-Filled Steel Tube structure void and the self-stress is an urgent problem. Basis on the Western Transportation Science And Technology Projects《Self-stressing Concrete Filled Steel Tubular Arch Bridge Test of Development and Application(Contract No.: 2006 318 814 22)》, the following researches have been completed in this paper.①Logicizing the current detection method, the main parameters on the impact of test results were analyzed in ultrasonic detection; By comparison of existing ultrasonic detection methods, the applicable conditions and detection accuracy were analyzed .②Detection of systematic ideological void has been presented, which test the void type of qualitative fistly, then detect the void scope of quantitative in concrete ultrasonic testing of void, the two should be combined with a comprehensive identification.③The first formula of test steel-concrete interface debonding range is presented.④The derivation conditions and reasonable assumptions were analyzed by conclusion of the existing theory of self-stress calculation method;The difference between laboratory test and the real bridge test of self-stress have been analyzed, it has maked a preliminary attempt to bridge the achievement of the practical test.⑤For the lack of shrinkage and creep test data in the practical test, the expected idea and the expected formula for the bridge creep has been proposed; Considering temperature affect from environmental temperature and hydration heat of concrete, the principles and methods is proposed in the self-stress test.Finally, the difficulties and shortcomings of the void detection and self-stress test were summarized in the present, it put forward advice for further research on the works of these two aspects and prospect on this basis.