Experimental Study On Seismic Behavior Of High-strength Concrete Columns With Expanded Metal Lath

With the popularization of high-rise and super high-rise buildings and the developments of long-span and overloading structure systems,the high-strength materials,especially high-strength concrete,are chosen to use in actual project both at home and abroad.However,high-strength concrete is a kind of brittle material whose component ductility has flaws.In order to improve the function of high-strength concrete,this study tries to add expanded metal lath confinements to the plastic hinge at the end of columns.Through the effective confinement of expanded metal lath,the strength and ductility of concrete columns would be improved and dissipated energy dissipation under seismic load would be strengthened.Main contents as follow:(1)This study puts forward structural measures and operational methods for adding expanded metal lath confinements to the plastic hinge at the end of columns during the actual projects.Using existing theories to analyzes the confinements of expanded metal lath to the plastic hinge at the end of columns.(2)Low cyclic reversed loading tests for 4 reinforced concrete column test specimens with 200mm×200mm sectional dimension,an axial compression ratio of 0.4 and confined on the surface and interior respectively with expanded metal lath are conducted to evaluate the seismic behavior of HSC(high-strength concrete)columns confined with expanded metal lath.The failure process,failure modes,hysteresis characteristics,ductility and dissipated energy dissipation are investigated in this paper.The results of experiments of specimens with different confinement methods indicate that the horizontal bearing capacity and dissipated energy dissipation of specimens could be improved significantly by employing expanded metal laths to confine the high-strength concrete columns on their surface.Owing to the mesh unit of expanded metal lath chosen in this study is small,inside confinements give rise to the separation of concrete in the core area and weaken the ductility and dissipated energy(3)The stress analysis of solid model is established using finite element software ABAQUS and experiments,using concrete damage shaping model,and introduce the damage factor,based on the experimental phenomena and the experimental data and simulation results were compared to verify the accuracy of finite element simulation.