Wen Jing Wang

Experimental Study on Axial Compression Performance of Full-Scale Square Columns of Reinforced Concrete Confined by High-Strength Reinforcement Hoops

Axial compression experiments of four full-scale reinforced concrete columns of two groups were carried out. One group of three columns used high-strength steel with the yield strength of 1000MPa as reinforcement hoops, and the second group used the ordinary-strength steel with yield strength of 400MPa. The axial compressive performances between these two groups were assessed. Compared to the specimen using the ordinary-strength steel, the axial compressive bearing capacity of using the high strength steel dose not increase significantly, while the deformation ability increases greatly. The results also indicate that the stress redistributions of the hoops and the concrete sections are obvious, and long-lasting when specimens achieve the ultimate bearing capacity after the yield of the rebar and local damage of concrete materials, at this time the strain of the specimens developes a lot, especially stress - strain curves of speciments with high-strength hoop all show a wide and flat top.

Seismic Performance of Steel Beam-Column Joint under Low Cyclic Loading with Multiple Cycles

An experiment of three T-shape beam-column steel joints with intensive cover plate was conducted under low cyclic loading with different cycle numbers, to study seismic performance of the joints subjected to long-period ground motions. Effects of cycle number on mechanical performance and length of plastic hinge were analyzed. The results show that as the cycle number increases, capacity of the joint decreases, and plastic hinge of the joint develops longer which appears closer to the cover plate, and the platform of skeleton curve grows longer, and the stiffness attenuates slightly.

Dynamic Response of Frame Structure with Different Stiffness in Two Horizontal Directions under Oblique Seismic Action

The ground motion is multidimensional, random and uncertain in directions when earthquakes occur, so dynamic response under oblique seismic action needs to be considered in the structure design. A frame structure with different stiffness in two horizontal directions was analyzed under seismic action with different input angles. The maximum response of beams and columns was obtained. The seismic mechanism of structures under oblique seismic action was discussed.

The FEM Analysis of Mechanical Properties of RC Short Columns under Oblique Horizontal Seismic Action

Simulation analyses of RC short columns are conducted under oblique horizontal seismic action monotonically using ABAQUS software. Concrete damaged plasticity model is used for concrete. Ideal elastic-plastic model is taken for steels. The results show that when the axial compression ratio was relatively low, the capacity of the columns increased with the increasing of load angle, because of the effect of tensile bars. For the relatively high axial compression ratio, the bearing capacity decreased with the increasing of angle, because of the effect of concrete in compression area.

Finite Element Analysis of Reinforced Concrete Beam-Column Joint under Low Cyclic Loading with Different Load Systems

Seismic performance of RC beam-column joints under low cyclic loading with different cycle numbers was analyzed by FEA software, to study duration effect of long period ground motion. The loading with different cycle numbers was used to simulate the duration of the ground motion. Hysteretic curves and skeleton curves of the joints were obtained. The results indicate that as the cycle number increases, the capacity and ductility of the joint declines, and the stiffness of the joint attenuates faster.

Failure Mechanism of a Steel Frame under Oblique Seismic Action

Pushover anlysis of a three-story one-span space frame under oblique seismic action was conducted using ABAQUS software. The loading angle is 0°, 15°, 30° and 45° respectively. Failure mechanism of the space frame was analyzed, such as yield sequence of beam end and column end, and force-displacement curves. The results indicate that the structure loaded with angle of 0° failed when beam hinge appeared. With the increasing of load angle, the failure mechanism of frame changed from beam hinge failure to column hinge failure gradually.

Bearing Capacity Calculation of Full-Scale Reinforced Concrete Beam-Column Joints Based on a Strut-and-Tie Model

Based on test results of two full-scale reinforced concrete beam-column joints, carrying capacities of core areas of the joints were calculated and modified based on the strut-and-tie model. The results indicate that the capacities calculated with h-D-regions is smaller than those with h/2-D-regions, and the calculated results with h/2-D-regions agree better with the test results.

Experimental Research on Full-Scale Reinforced Concrete Columns with Strong Confinement under Concentric Compression

To investigate the axial compressive behavior of reinforced concrete columns with strong confinement, a total of five full-scale reinforced concrete columns with stirrup characteristic values in the range 0.22~0.47 and section dimension 600mm×600mm were tested under concentric compression loading. The test results indicated that all specimens failed in a similar way. The longitudinal bars buckled in compression; the peripheral stirrups bowed out and several stirrups fractured; the cover concrete in the mid-height section of specimens spalled seriously; however, the core concrete of specimens was not crushed. The axial compressive bearing capacity and deformation ability of reinforced concrete columns could be improved by strong confinement. When specimens reached the ultimate bearing capacity, the longitudinal reinforcement yielded and provided axial bearing capacity for specimens; the transverse reinforcement reached tensile yield strength and provided effective confinement for the core concrete.

The FEM Analysis of Size Effect on Prism Concrete Specimens with Different Lengths under Loads of Axial Compression

Four prism concrete specimens with same height, same width, but different lengths is simulated in using ABAQUS FEM analysis software. The simulation work is conducted under monotonic axial compression loading, and its purpose is to research the size effect of prism concrete specimens, primarily to study the effect of specimen length on the axial compressive strength. The stress-strain relation of the specimen is analyzed. The results indicate that, for different lengths of specimens, their axial compressive strengths are quite different and the size effect on them is much obvious. The compressive strength improves gradually with the increasing of length, and size effect on transverse and vertical constraint stress of core concrete area is much distinct as well. Meanwhile, it can be obtained that the standard design method of the structures and components is conservative and of adequate security.

Research on Horizontal Bearing Capacity of High-Rise RC Shear Wall Arranged High-Strength Steel in Boundary Concealed Columns

Based on the plane-section assumption, the formulas of yield moment and ultimate moment are derived for calculating high-rise RC shear wall. High-strength steels are used as transverse and longitudinal steels in boundary concealed columns of the shear wall. The practical application is performed by using the formulas derived for calculating horizontal bearing capacities of four specimens, in which one specimen used ordinary-strength steel and the others used high-strength steel. Meanwhile, the numerical simulation is carried out on the four specimens by finite element method, and the results show that the horizontal bearing capacity of the shear wall increases obviously for specimens using high-strength steel in boundary concealed column, and the simulation results of finite element method are in good agreement with formula results.