| There are important theoretical and actual values to study the dynamic plastic response of clamped square plate for anti-explosion design of protective structures. This paper made a theoretical analysis to the dynamic plastic response of clamped square plate subjected to blast loading, by employing moving hinge theory and rigid-plastic constitutive model. By compared the theoretical analyses with numerical simulation and literature experimental study, the feasibility of moving hinge theory have been verified. The main contents are as follows:1,The formation process and characteristics of the moving hinge was introduced by the study of the response of a cantilever beam subjected to an impulse load at the free end.2,The blast load was simplified to the triangle load which has an ascent portion and descent stage, and was exerted on the square plates as uniform load. Meanwhile the load was divided into high load and moderate load, according to the moving of the plastic hinge line. Studies indicate that with increasing load intensity, clamped square plate under blast loading exhibit four motion mode, and the final deflection formula of the plate midpoint have deduced for the four motion modes.3,In the high load cases, the moving plastic hinge lines were formed in the clamped square plate. The moving law was analyzed for the moving hinge line with the change of load, and the analytical expressions of the position of moving hinge line were obtained. The plastic zone near the plate center was determined by the turning points of the moving hinge lines.4,The dynamic plastic response of clamped square plate subjected to blast loading is studied numerically by the fluid-solid coupled method. The numerical simulation reproduced the propagation of the blast shock wave and the transient process of the stress and strain in plate. The equivalent stress obtained by the simulation is found to be similar to those obtained theoretically.5,The mid-point deflection formulas were verified by both experimental and simulation results. The analysis shows that the calculation values are in basically agreement with experimental data and numerical simulation results within the first three motion mode. |
