| The strength and behavior of traditional composite slabs are governed by the shear interaction between the concrete and the steel deck.The interaction property depends on several factors,so as to further study the interaction between them.Therefore,the interaction between them can be analyzed by finite element model and full-scale experimental design method.ECC has the advantages of high toughness,high ductility and strong synergistic deformation ability with reinforcement bars.Therefore,the profiled steel sheet-ECC composite slab system was proposed.In order to study the longitudinal shear behavior between profiled steel sheet and high tough-ness ductile concrete.Eight full-scale specimens of ECC-profiled steel sheet composite slabs were designed in our group.Static loading tests were carried out on all specimens to investigate the effects of the thickness of composite slabs and profiled steel sheet,the shear span,end anchorages on the mechanical properties and failure modes of ECC composite slabs.Finally,the results show that the longitudinal shear resistance of the ECC composite slab increased with the increase of the thickness of profiled steel sheet and composite slab,the failure mode of ECC composite slab can be changed by setting up shear studs at the end of the ECC slabs.According to the comparison the m-k method between Eurocode 4,CECS273:2010 and ASCE,the calculation method of ECC composite slab was selected.The Eurocode 4 is more suitable.Additionally,the longitudinal shear resistance of ECC composite slabs can be calculated by using m-k method,based on the Eurocode 4,where the m value is 229.44 MPa and the k value is-0.0942 MPa.In generally,the calculation results agree well with the test results.A finite element model of ECC composite slab with end anchorages was established by using ABAQUS software.The accuracy of the model is verified by the experimental results,and choosing the appropriate material constitutive model.According to the test data,Connector element was selected and the appropriate constitutive relationship of the connecting element is determined by force balance method.The results show that the simulation method is feasible and the simulation results are in good agreement with the experimental results.Finally,based on LTPR-1 specimens,a variable parameter study was carried out to study the effects of ECC strength,the strength of the shear studs and profiled steel thickness on the longitudinal shear resistance of ECC-profiled steel sheet composite slabs.The results showed that the ECC strength and the thickness of profiled steel sheet had significant influence on longitudinal shear resistance,while the strength of end anchorages had little influence on it.In addition,in order to explore whether the interaction between shrinkage profiled steel sheet and ECC has a greater impact on the shear bond bearing capacity of composite slabs.ECC material was used instead of the traditional concrete,and the Force Equilibrium method was used to obtain the shear force-slip curve of the steel sheeting-ECC composite slab.Through the curve,the contact between ECC and the profiled steel sheeting can be reasonably considered,and the FE model was established.The finite element model of ECC composite slab was used to analyze,the longitudinal shear resistance,and the finite element analysis results agree well with the experimental results.Additionally,referring to the calculation method of longitudinal shear resistance of profiled steel sheet-ECC composite slab,a formula for calculating the longitudinal shear resistance of ECC composite floor was proposed.Finally,the finite element model was used to analyze the parameters of different shear spans,profiled steel sheeting thickness and the strength of ECC.The results shown that these parameters have great influence on the longitudinal shear behavior of ECC composite slabs. |
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