Reseaerch On Low Yield Point Steel’s Dynamic Constitutive Model And Its Explosive Performance

The explosion usually causes incalculable damage to human life and propertysafety, whether in the local war or everyday life, the design of explosion and shockresistance in the building structure is very important. Recently, many scholars haveproposed a suitable structure which used energy consumed strongly material as theenergy absorbing device, compared with the traditional concept of simply increasingthe structural stiffness, the method is more economical and reasonable.Low yield point steel (LYP) has low yield strength and high elongation rate.Moreover, its plastic performance and impact toughness are better than generalstructural steel. In view of Q160-LYP’s good plastic deformation capacity, this articlestudied its antiknock performance, which mainly includes the following content:(1) Q160-LYP’s mechanical property was tested by quasi-static experiment andSHPB experiment, in addition, Johnson-Cook constitutive model was fitted usingstrain hardening rule in quasi-static conditions and strain rate hardening rule indynamic conditions. Based on the constitutive model parameters, dynamic yieldstrength and DIF tendency were analyzed.(2) Numerical simulation of SHPB experiment process was carried out usingfinite element analysis software LS-DYNA. Reasonable element size and contactstiffness penalty factor were determined. J-C model parameters were verified to beaccurate by comparing with the dynamic stress-strain curves obtained from SHPBexperiment and simulation.(3) The result of Q160-LYP for explosion energy absorption was studied anddynamic mechanical response was obtained by both fluid-structure interactionalgorithm and equivalent triangular wave algorithm. Compared with plates made ofdifferent steel (Q235, Q345, Q460) through energy analysis method, Q160-LYP’ssuperiority of energy absorption and energy consumption was confirmed.