Seismic Performance And Bearing Capacity Study On T-short-pier Shear-masonry Composite Wall

T-short-pier shear-masonry composite wall is a novel combination of compositewall with large initial stiffness and ultimate bearing capacity. The parts of the compositewall could work together with good performance and multi-channel of seismic defense.Quasi-static test of composite wall was conducted by our team previously and somevaluable conclusions were got. However, the analysis of its seismic performance wasnot deep enough, and the research on ultimate bearing capacity of normal cross sectionwas lacked. In this paper, a positive study on seismic performance and ultimate bearingcapacity of T-short-pier shear-masonry composite wall is done.The main contents are asfollows:(1)Failure mode, hysteresis curve, ductility, stiffness and other mechanicalcharacteristics of the three-pin composite wall FW-1, FW-2and MFW-1were fullyanalyzed; The ABAQUS numerical model was used to simulate the loading process ofMFW-1. The comparative analysis of the process and morphology, skeleton curves, loadfeature point and ductility was done,and the numerical calculation results were in goodagreement with the experimental results. The reliability of the numerical model wasverified.(2)The numerical models for composite walls of different limb-thickness ratio(3-Pin),different axial compression ratio(5-Pin),different depth-width ratio(3-Pin)wereestablished. Failure modes of walls in different parameters, seismic performanceindicators as capacity, characteristic value of load, ductility, stiffness degradation wereanalyzed. The conclusions are as followings:1) The effect that different limb-thicknessratio,depth-width ratio of wall act on failure mode, bearing capacity, ductility andstiffness degradation for combined wall is great. The effect that axial compression ratioacts on the ductility of combined wall is great.2) The larger limb-thickness ratio is, the greater bearing capacity of the wall,and the greater the ductility increase is within acertain scope. The stiffness degradation degree is greater and the plastic damagehappens in the structure. With the decrease of axial compression ratio, the ductility ofthe combined wall increases and the stiffness degradation becomes larger. The plasticcollapse is more prone to happen to the structure within the scope of the reasonableaxial compression ratio. The less depth-width ratio is, the greater the bearing capacity ofwall and the better the structural ductility to be. Also the slower speed stiffnessdecreases, the plastic collapse is more prone to happen.3) Results of analyzing thefailure modes of each model, ductility, stiffness and other aspects of the composite wallshowed that the wall limb, coupling beam and masonry wall could work together as ateam-work. Multi-channel seismic lines were formed.The capacity to resisttransformation and the energy dissipation ability were strong. The structural ductilitywas good and the structure was suitable for small high-rise residential dwelling inshort-pier shear wall structure system.(3)The method of equivalent stress graphics was used in this paper and theequivalent coefficient was calculated.The boundary height of pressure zone was given.Compressive strength formula of ultimate bearing capacity for normal section wasdeduced from the T-short-pier shear-masonry composite wall in the high-level buildings,including large and small eccentric ultimate bearing formula of large eccentriccompression. This formula is used to guide the reinforcement of composite wall.