Parametric Study On Post-installed Anchorage Under Combined Action Of Earthquake And High Temperature

In recent years,post-installed anchorage has been widely applied in China,the connection technology has not only been applied to civil engineering but also in equipments or facilities connection of lifeline engineering,so the anchorage performance is very important to the building structure.In this paper,in order to understand the structural behavior of post-installed anchor between steel and concrete under the combined action of earthquake and fire,a numerical method has been employed for parametric analysis.The ABAQUS software was used to simulate the seismic performance and fire resistance of the post-installed anchorage joint of steel-concrete under cyclic loading and thermo-mechanical coupling.In addition,performance-based design method was used to determine the behavior of steel-to-concrete post-anchorage joint.The main conclusions are presented as following:(1)This paper has investigated with consideration of three different embedment depth for steel-to-concrete joint,simulated and analyzed the seismic performance of three different anchoring depth of post-installed anchorage joint by using ABAQUS,the characteristic of damage state,hysteretic curve,skeleton curves and ductility have been studied to explore influence of anchoring depth on seismic behavior.It concluded that the ultimate bearing capacity and seismic behavior of the anchor joint can be improved by increasing the embedded depth.(2)This paper simulates and analysis the action of fire and thermal-mechanical coupling on the post-installed anchorage joint of steel-concrete,to explore the fire protection layer thickness ranging from 60 mm to 25 mm on the performance of post anchored joint of steel-concrete after fire.Meanwhile planting bar embedment depth of 15 d,20 d and 25 d for different fire protection layer have been also studied in the thermal-mechanical coupling analysis.Increasing the depth of embedded steel bar and the thickness of fireproof layer in certain range can improve the ultimate bearing capacity and the fire resistance limit of the post anchorage joint.(3)In order to study the breakage of the post-earthquake fire protection layer for high temperature performance and bearing capacity of the post anchored joint of steel-concrete,design damage model for fire protection layer,analyses the high temperature performance of the model with damage thickness of 5mm-40 mm and breakage length of100mm-600 mm,and research the model under thermal-mechanical coupling action,explores the influence of damage length and thickness of the damage to the performance of the post anchored joint of steel-concrete.(4)Consolidation of the simulation results,the application of performance-based design method for anchor nodes,determine the performance design index and put forward the performance level,and for the design of anchorage node corresponding seismic and fire design proposal.