Study On The Behavior Of Short Columns Of Glass Concrete Filled Steel Tube Under Axial Compression

At present,China’s infrastructure construction is in full swing,and the annual consumption of concrete is particularly large.As the traditional components of concrete,cement and natural sand consume more and more.The production and exploitation of cement and natural sand have a negative impact on the environment.Therefore,it is very urgent to find substitutes to replace cement and natural sand in concrete.In this paper,the glass powder with a certain particle size after grinding waste glass is used to replace cement and natural sand,and the processed glass beads are applied to the production of concrete-filled steel tube,providing a way for environmental protection and waste recycling.On the basis of previous studies,glass powder and glass beads were soaked for 3 hours before concrete mixing.After mixing,the workability of the concrete is improved significantly,and the glass bead improves the workability of the concrete significantly.The bond between glass beads and concrete components is good,and the distribution of glass beads in concrete is uniform.The strength of concrete with glass increases rapidly in the later stage.From the strength data obtained in this test,15% replacement rate is the best.There is pozzolanic activity in ground glass powder and ASR reaction in concrete,both of which are related to water.In this test,the expansion of concrete was measured for 28 days,and it was found that the expansion of CFST was not large,and the expansion of part of concrete with glass in the steel tube was lower than that of ordinary concrete.The mixing method used in this test will not cause obvious alkali silica reaction of concrete.According to the results of the axial compression test,the best replacement rate of CFST is 10%.By fitting the bearing capacity of CFST with the replacement rate,the fitting formula of the bearing capacity of replacement rate is obtained.At present,there is no relevant research results in the constitutive model of glass concrete.This finite element simulation uses two widely used constitutive models to simulate the concrete filled steel tube.The results of 10%,15% substitution rate are consistent with the test data.The results of 20%,25%,30% substitution rate are quite different from the test results.According to the results of this experiment,when using the finite element method to simulate the glass concrete,the substitution rate of ordinary concrete constitutive model simulation is within 15%,and the data obtained is more accurate.