Study On The Explosion Area Of RC Frame Structure Reinforced Explosion Relief Composite Wall Under The Action Of Implosion

RC frame structure is widely used in the existing civil buildings in our country.At present,the destructive effect of explosion load on the structure is generally not considered in the structural design of these public buildings.The damage degree of structure,property loss and casualties are serious under the action of internal explosion.It has been proved that the way of strengthening the composite wall can effectively reduce the damage degree of the structure,and the research on the explosion area is rare.Therefore,in order to reduce property losses and casualties,this paper studies how to set a reasonable explosion area for RC frame structure public buildings to dissipate the energy of explosion shock wave.The research contents and conclusions are as follows:(1)Through Pro-E,Hyper Mesh,Ansys-Lsdyna and LS-Prepost,the frame structure model is established,calculated and post processed,and the literature is consulted for comparative analysis to determine the explosion analysis method,material model,key parameters and failure criteria for numerical simulation.(2)The frame structure with explosion test is studied by numerical simulation,and the failure mode of the structure after explosion and the pressure time history curve of the measuring point in the center of the wall with opening are analyzed.The results show that the failure mode of the numerical model is similar to that of the test structure;The variation trend of pressure time history curve is consistent,and the error of pressure peak point is small,so the numerical simulation method selected in this paper is more reasonable.(3)For the second floor 1×1 The influence of the existence of the wall on the damage degree of the 1-span frame structure is analyzed when the explosive quantity is 40 kg,60kg and 120 kg respectively.Through the analysis of the failure mode of the simulation results and the pressure time history curve of each measuring point,it is known that the existence of the wall on the non explosive layer has little influence on the structural failure degree.Therefore,in the follow-up study,it is not necessary to establish the wall on the non explosive layer of the frame structure.(4)Two kinds of frame models of ordinary concrete block wall and foam concrete infill wall under different explosives are established respectively.The explosive values are20 kg,40kg,60 kg,80kg,100 kg,120kg,140 kg,160kg,180 kg.The numerical simulation of two different types of wall models with the same explosive quantity is carried out.Through the comparative analysis of the simulation results,it is finally determined that the explosive quantity suitable for the model studied in this paper is 120 kg.(5)120kg explosives were placed in the center of corner room,middle room and corridor with different areas.For each type of room,three different wall setting methods are used to determine the more reasonable explosion relief area: the explosion relief area determined by the hole of the wall when the walls are all ordinary concrete block walls;Only the room where the explosive is located is equipped with the explosion relief area determined by the reinforced explosion relief composite wall;Considering the influence of blast wave on adjacent rooms,the area of explosion release is determined.Through the comparative analysis of the failure mode of the structure,the air pressure time history curve and the maximum principal stress time history curve of the measuring point position under three different wall setting modes,the more reasonable explosion relief area range of each type of room is obtained.