Experimental Research And Finite Element Analysis Of Progressive Collapse Resistance Of Reinforced Concrete

The integrity security of the structures in the structural design is very important.How to avoid the construction structure continuous collapse caused by accidental loads such as terrorist attacks, explosion, fire and other emergencies has become a hot topic of architecture. From the Ronan Point apartment destructed in the 1960 s to the collapse of World Trade Center in the United States in 2001,This collapse caused by the disproportionately large area due to the partial failure has caused tremendous damage to human beings. In view of this, the continuous collapse of the structure has done a lot of research at home and abroad. Reinforced concrete frame flexible layout,overall good and is widely used all over the world. Due to the complex process of collapse of the force mechanism, relevant research framework for progressive collapse is still not perfect, and need to carry out experimental research and finite element analysis.(1)The experimental study of continuous collapse of reinforced concrete frame structure. In this paper, the authors design a 2 x 2 layer of reinforced concrete frame model, through the hydraulic jack for failure Angle to the outside world, and simulated the continuous collapse process of frame structure by using hybrid control force and displacement loading method. Observe the Angle collapsed failure process and plastic hinge form development. Collect the date of resistance, reinforcement and concrete strain.(2)The characteristics of resistance to the continuous collapse of reinforced concrete frame structure was analyzed. According to the experimental data andphenomena, structure force- displacement curve、The order and quantity of plastic hinge and the mechanism of Collapse failure was analyzed. Framework in the process of failure collapse Angle has experienced the elastic stage and plastic stage and failure stage, through the column of framework bending bearing capacity to provide continuous collapse resistance.(3)Using ABAQUS finite element software to simulate the process of continuous collapse of reinforced concrete frame structures prism failure, resistance curves, steel and concrete stress curve has been got and were compared with experimental results. The simulation can better simulate the process of continuous collapsed of the model, reveals the process and mechanical characteristics of frame structure Angle failure under collapse.(4)On the basis of the corner posts failure simulation, using ABAQUS to simulate and analysis the progressive collapse process and discuss the collapse of the force during the conversion mechanism, when the long side of the column failure of reinforced concrete frame structure. The simulation results show that during the conversion process of column failure framework has experienced the elastic stage,stage of formation of plastic hinge, concrete damage and suspension cable. The beam in frame failure area has experienced the conversion process by bending to the suspension cable to provide continuous collapse resistance.(5)The difference of collapse mechanism of corner column failure and the middle column failure is comparative analysised. When the angle fails,the beam of fail region with bending effect to resist external loads, although the edge of column fails, the frame beam has gone through the beam mechanism to convert the process of catenary mechanism. The different collapse mechanism is due to the different constraints of the failure area.