Research On The Damage Effect And Evaluation Method Of Invasive Warhead On Typical Buildings

More than 70% of the targets in the modern land battlefield are solid targets represented by underground fortifications,buildings,bridges,etc.Among them,buildings are becoming one of the main targets on the battlefield as a typical representative.The invading warhead is to deal with such solid targets.The main means of goal is becoming the main weapon of the world’s major military powers.The invading warhead mainly relies on the fragmentation field,shock wave field and other damage fields formed by the explosion after penetrating the protective layer to a specified depth to damage the target.Based on the damage to the whole and structure of typical buildings caused by the explosive load generated by the invading warhead,this paper firstly analyzes the vulnerability of typical buildings to obtain damage to trees and vulnerability of typical buildings,and selects reinforced concrete columns as vulnerable Damage the structure;then,according to the similarity theory,the similarity law of the explosive damage power field and the structure damage response is obtained.Then through the numerical simulation calculation and experimental verification of the damage effect of the explosion impact load on the reinforced concrete column under the same blasting distance but different proportional distances and the same proportional distance and different blasting distances,the following phenomena and laws are obtained:（1）Under the same proportional distance,with the increase of the charge,the peak overpressure remains unchanged,and the positive pressure action time increases;at the same explosion distance,with the increase of the charge,the peak overpressure increases,and the positive pressure acts Time unchanged（2）The type of explosion produced by the close explosion is impulse load.The impulse of the explosion impact load is closely related to the damage response of the reinforced concrete column.The damage response level of the reinforced concrete column under the action of the explosion impact increases with the increase of the impulse.Local damage changes from crack damage to avalanche damage,and overall damage changes from bending damage to bending shear damage;（3）The occurrence of cracks is related to the impulse of the explosive impact load.The displacement of the cracks has a tendency to spread outward with the increase of impulse,and when the cylinder undergoes bending failure,the range of occurrence is the mid-span.When the column is broken by bending and shear,the resulting area is the center of the column and both sides.The greater the impulse,the higher the damage level,the intensified crack propagation,the more the number of cracks,and the cracks gradually expand towards the fixed fulcrum.Finally,according to the test data,two dimensionless parameters,the proportional coefficient of the mid-span damage range to characterize local damage and the residual deflection to characterize the overall damage,are proposed.Engineering calculation formula,combining engineering calculation formula with experiment and simulation,put forward impulse damage criterion of reinforced concrete column under explosive load.The above conclusions have strong reference value for the subsequent research on the structural damage and anti-blast design of buildings under impact loads.