Research On The Method Of Penetrating Reinforced Concrete Multi-layer Target

With the rapid development of intelligent and dexterous penetration weapon system,it has become a research focus and difficulty to achieve accurate damage to important military targets with layered fortifications.In this paper,the method of layer counting for penetrating multilayer reinforced concrete target was taken as the research object,the layer counting method and burst point control scheme for penetrating multi-layer reinforced concrete target based on magnetic signal and overload signal were proposed.The overload characteristics and magnetic signal characteristics of projectile penetrating multi-layer reinforced concrete target were numerically simulated by LS-DYNA and COMSOL finite element analysis software.The scheme proposed in this paper provides a design reference for solving the problem of layer counting and burst point control of penetrating multi-layer targets.In order to solve the problem that the overload acceleration signal is conglutinated when penetrating multi-layer target,and it is unable to achieve accurate layer counting,a target layer recognition method based on magnetic detection technology was proposed,which avoids the signal conglutinated phenomenon in the method of using overload acceleration signal for layer counting,and improves the stability and accuracy of multi-layer target layer recognition.Combined with theoretical calculation and simulation analysis,the shielding effectiveness of missile material to magnetic signal was introduced.The magnetic field simulation models of projectile penetrating into three-layer reinforced concrete target normally and obliquely were established,and the change of magnetic field intensity of fuze part in the process of penetration was obtained.Through comparative analysis,it was concluded that the magnetic signal in the process of penetration is a physical field signal related to displacement.The influence of different steel bar density and projectile material on magnetic signal was considered,and the environmental adaptability of magnetic detection was analyzed,and the influence of ferromagnetic interference medium on magnetic signal in penetration process was obtained.The principle prototype of magnetic detection was designed and verified by laboratory experiments.Combined with the simulation and experimental results,the feasibility of target layer identification method based on magnetic detection technology and the accuracy of environmental adaptability simulation results were verified.The overload characteristics of projectile penetrating into multi-layer concrete target were numerically simulated and analyzed by using separate modeling and coupling algorithm,which solving the problem of accurate residual velocity of projectile after penetrating into concrete target.The numerical simulation models of projectile penetrating single-layer reinforced concrete target,three-layer reinforced concrete target with normal penetration and oblique penetration were established.The overload acceleration characteristics of projectile and fuze were obtained by simulation.Through the analysis of overload characteristics of fuze,it was concluded that in the process of projectile penetrating multi-layer reinforced concrete target,due to the structural response of projectile body,high frequency oscillation signal will be generated and superimposed with overload signal,which makes the overload signal of fuze appear adhesion phenomenon,resulting in the layered characteristics are not obvious,and it is unable to judge the time of projectile entering and leaving the target accurately.Based on the analysis of penetration overload signal and magnetic anomaly signal,a research scheme of layer counting precise burst point control based on the combination of magnetic anomaly signal and overload signal was proposed.Through the joint analysis of the magnetic signal and overload signal in the process of penetration,the discrimination of the entry and exit points of the projectile and the control strategy of the precise explosion point between layers were proposed in the case of penetrating multi-layer reinforced concrete,which improves the reliability of target recognition and the accuracy of the precise explosion point control after the target.