Research On Concrete Core Walls With Concrete-filled Steel Tube Reinforced Concrete Columns

Composite structures，which combine concrete and steel rationally,is a new form ofstructure between reinforced concrete structures and steel structure.It can take full advantagesof the two materials and compensate for each other’s disadvantages.Thus such a structure hassuperior mechanical properties over the traditional concrete and steel structures and canachieve better economic benefits.As a result,composite structures are now widely used inhigh-rise buildings.Frame-core walls and tubes in tube structure are common forms inhigh-rise building structures.In the design of high-rise building structures，loads are mainlycontrolled by the horizontal seismic load or wind load.What’s more,China is located on anearthquake-prone zone,the main horizontal force resisting member in a structure,core wallsdesire more in-depth research and the optimization of their mechanical properties is full ofengineering significance.This paper use the means of numerical simulation by the ABAQUS finite elementsoftware to conduct nonlinear FE analysis on the seismic performance and its influencingfactors of the concrete-filled steel tube reinforced concrete columns and composite core wallswith concrete-filled steel tube reinforced concrete columns.The main contents in this studyincludes the following：(1) Using the ABAQUS finite element software to simulate concrete-filled steel tubereinforced concrete column model SS1、SS2and SS3in a experiment to resist the monotonichorizontal load and cycle horizontal load; compare the calculated mechanical properties withthe experimental results,and verify the finite element software can reasonably simulate suchmembers.(2) Simulate the performance of concrete-filled square steel tube reinforced concretecolumns with square section and circular section and concrete-filled circular steel tubereinforced concrete columns with circular section under the action of monotonic horizontalloads,and then compare the load-displacement curves,crack development,ductility and cycliccurves of these columns with three different sections and discuss the impact of axialcompression ratio and longitudinal stiffener.(3) Using the ABAQUS finite element software to simulate composite core walls modelCT-1and CT-2in a experiment under the action of monotonic horizontal loads， compare themechanical properties of the calculated results with experimental results,and verify the finiteelement software can provide reasonable results. (4) Based on the studies on concrete-filled steel tube reinforced concrete columns and onthe core walls model CT-1and CT-2,the study proposes a new type of concrete core wallswith concrete-filled steel tube reinforced concrete columns，and compares its mechanicalproperties under general monotonic horizontal loads with model CT-1and CT-2by ABAQUSfinite element software.Then, the effects of the reinforcement ratio of shear walls，steel ratioof columns，steel ratio of concealed truss in shear walls and steel ratio of concealed plate incoupling beams impact strength,stiffness degradation,ductility and energy dissipation capacityof model CT-3，on which loading general monotonic horizontal force，oblique monotonichorizontal force and5%level eccentric monotonic force on the simulated results arediscussed.Suggestions regarding structure design are provided based on the results of thisstudy.