Abstract Abstract: This article is based on the displacement mode which put forward by Reissner type theory, to amend the soft sandwich hypothesis, puts forward a hard sandwich hypothesis, namely to considering the Sandwich layer’s in-plane stiffness and bending stiffness, get the geometric equations and physical equations of hard-sandwich plate, established the balance differential equation of the hard sandwich interlayer board structure which in the in-plane parallel loads. Simplify the equation, got the analytical solution of the hard sandwich interlayer board structure’s critical load which under the condition of four simply supported, and calculate the influence of the sandwich layer material’s elastic modulus, thickness, Poisson’s ratio and density on hard sandwich board’s critical load, the results show that, the sandwich layer’s in-plane stiffness has great influence on the critical load, consider the in-plane stiffness is necessary.
2013, Vol. 34 
