Research On Seismic Behavior And Performance-Based Seismic Design Theory Of Steel High Performance Concrete Structural Walls

Steel high performance concrete structural wall was a combination of steel and high performance concrete.They can give full play to the advantages of steel and concrete and have better dynamic behavior,such as ductility and ability of dissipating energy than high performance concrete structural walls.However,the resrarch on the seismic behavior of SHPC structural walls is rare.The seismic behavior and performance-based seismic design method of SHPC structural walls are investigated by experiments and theoretical analysis,then the performance-based seismic design methodology is applied to the design of SHPC structural walls in this paper.The main contents covered are presented as follows.(1) Six specimens of steel high performance concrete structural walls are constructed and tested under low cyclic reversed lateral loading.Some parameters, shear span ratio,axial load ratio,stirrup ratio are taken into consideration.The main failure patterns as well as hysteretic curves of those walls are obtained,and influence of each of the parameters on the ductile behavior,ability of energy dissipation and law of strength degeneration are analyzed.(2) On the basis of theoretic formulas and testing data,a restoring force model of reversal skeleton curve of SHPC structural walls were established with degradation of strength and stiffness taken into account.The results show that the declined strength stage of skeleton curve of specimens is related to the yielding strain of boundary steel, axial load ratio and stirrup content.(3) The fiber wall element model in CANNY program is used to analyze the non-linear performance of SHPC structural walls.Analysis results are very agreement with their test results and it proves that he fiber wall element model is reasonable and efficient in the nonlinear analysis of SHPC structural walls.Also,some parameters which were concered on seismic behavior of SHPC structural walls were analyzed by CANNY program.(4) Based on experiment of SHPC structural walls under low cyclic reversed loading, the calculating equations of crack loading,section compressive load-bearing capacity and inclined section shear load-bearing capacity were established.The comparison of calculation results and test results illustrates that those calculating procedure is feasible.(5) The yielding curvature and the ultimate curvature of SHPC structural walls are calculated by equilibrium and deformation condition.Then,the displacement ductility ratio of SHPC structural walls was established by the relationships between curvature ductility ratio and displacement ductility ratio.It is obtained for the relationships among the displacement ductility ratio,the axial load ratio,the characteristic value of stirrup content and the aspect ratio.It is concluded that the axial load ratio n is an important factor for deformation capacity and increasing the characteristic value of stirrup contentλv and limiting the axial load ratio n are effective means to improve ductility.The displacement-based deformation capacity design was then developed for SHPC structural walls and the conclusion can be referred by the evaluation of deformation capacity for SHPC structural walls.(6) On the bais of cyclic loading test of SHPC walls and SRC walls,the seismic performance of SHPC structural walls can be divided into four levels:performance continuity,performance interruption,life safety and collapse prevention.Based on the experiments and results of SHPC structural walls,the failure mode and characteristic are analyzed.Then,the limit state of the different seismic performance levels and their dominating parameters are proposed.Finally,the range of deformation limits of SHPC structural walls are developed for four different seismic performance levels.(7) Based on the deformation capacity of SHPC structural walls,its drift at yield and at ultimate were obtained.The performance-based seismic design method was then developed for SHPC structural walls and the transverse reinforcement characteristic value accordance with the target top displacement ratio and axial load ratio is proposed.