Dynamic Behavior Of Bolted Beam-column Connections Assemblies Under Impact Load

In recently years, due to the frequent disasters such as earthquake, explosion,terrorist attacks, structure was severely damaged under extreme load, collapse accidentoccurred frequently, causing heavy casualties and property losses, especially forimportant long-span and high-rise building. When the building collapsed, the damagewas incalculable. Under extreme load, structure will produce nonlinear largedeformation, failure of critical components may cause the failure of peripheralcomponents, leading to the collapse of the whole structure. Experimental studyresearch of common bolted beam-column assemblies were conducted to study theimpact mechanical properties using the high-performance drop hammer test machine inHunan University. And numerical analysis was carried by using the finite elementsoftware ABAQUS. The research work can be summarized as follows:(1) The experiment study of the impact mechanical properties of two endplatebeam-column assemblies and two T-stub beam-column assemblies were conducted, thefailure modes of different connections were analyzed. Law of development of specimendeformation and hammer impact in the process of impact was revealed.(2) The finite element model of endplate beam-column assemblies and T-stubbeam-column assemblies under impact loading was developed usingABAQUS/Explicit. The dynamic behaviors of the experiment were analyzed. Thenumerical results were in good agreement with the experimental results.(3) According to the finite element analysis results and the test data, the dynamicdevelopment models of catenary action of rigid beam-column assemblies andsemi-rigid beam-column assemblies respectively based on displacement were putforward. The value of estimated static platform can be got, and compare it with thevalue of the static analysis model, the results were in good aggrement. It shows that themodel obatained by finite element static analysis was reasonable.(4) The concept of the influence coefficients of resistance was put forward. It wasused to measure the contribution of flexural bearing capacity and axial tension capacityto the bearing capacity of structure of the specimen during different stages. Resultsshow that endplate beam-column assemblies in this paper have developed to a certain extent of catenary action within the scope of the test. For these specimens, bendingcapacity provided the primary resistance.