Long-Term Behavior of High-Performance Concrete-Filled Steel Tubes with Different Axial Compression Ratio
|School||Harbin Institute of Technology|
|Keywords||Concrete Filled Steel Tubular Following the flow theory Long-term deformation Creep Axial compression ratio|
Steel concrete has a high compressive bearing capacity and convenient construction , widely used in the arch . But the long-term loads , shrinkage and creep of the core concrete will cause the Rib section stress and arch redistribution of internal forces and lower rib rigid deformation increases , shrinkage and creep on the mechanical properties of the steel pipe concrete present study hot issues , but existing studies for steel pipes ordinary concrete . In this paper, a high-performance steel pipe concrete arch bridge in the widely used , mainly consider the effects of axial compression ratio of steel pipe of high performance concrete study of the long-term performance . Two sealed high-performance concrete axial compression specimens of the long-term load test and reusable creep test . Based on the experimental results comparative analysis of some typical long-term deformation of concrete under constant loads calculation model , the results show that the AFREM model is more appropriate to calculate the long-term deformation of confined high-performance concrete . Reusable sealed concrete creep test, using the following flow theory and combined with AFREM model to analyze the long-term deformation of steel pipe concrete members , to establish a long - term deformation formula . Long-term load tests for a period of four months eight steel high - performance concrete specimens , the main parameters of the specimen : steel ratio α = 0.08 to 0.136 , the axial compression ratio of n = 0.3 to 0.5 , the slenderness ratio λ = 12. Validity of the test results and the test results of others to verify the long-term deformation of the steel pipe of high performance concrete calculation formula . Analysis of axial compression ratio , the ratio of the steel and holders of long - term deformation of the loading time of CFST 6 long specimen is loaded and four pairs of ultimate bearing capacity of the test of the test piece , get some useful conclusions .