桥跨分析模型薄板剪力的精确计算

对于两对边简支、两对边自由的矩形析，经典薄板理论不能求得Ｑ的精确解，根源在于Ｋｉｒｃｈｈｏｆｆ变换剪力Ｖｙ＝０在静力等效上的局限性。对上述板，通过一个实例，用Ｒｅｉｓｓｎｅｒ中厚板理论和经典板理论的解做比较，发现苦自由边板的边界条件Ｍｙ＝Ｖｙ＝０用梁的边界条件Ｍｙ＝Ｑｙ＝０替代，就能得到与用Ｒｅｉｓｓｎｅｒ板理论相同的精确内力Ｑｘ，Ｑｙ。这样，就提供了一个科教片上述薄板精确剪力Ｑｘ，Ｑｙ的简化方法

EXACT CALCULATION OF SHEAR OF THE THIN PLATE MODEL FOR THE BRIDGE ANALYSIS

In this paper to discuss the rectangle plate which is simply supported at the opposite sides and free at the other sides, the exact solution of shear connot be obtained by the classical thin plate theory,since the Kirchhoff-Transformational shear V_y=0 is rather limited in statical balance equivalent. For above mentioned plate,through an example to make comparison between solutions of Reissner medium thick plate theory and of classic thin plate theory, it is found that if the plate boundary condition of free sides M_y=V_y=0 is taked the place of beam one M_y=Q_y=0,we can obtain the exact internal forces Q_x and Q_y which is the same as that by Reissner-plate theory. The paper puts forword a simplified method exactly calculating shears Q_x, Q_y for above mentioned plate,which will exert a greater practical value on improving accuracy of the shear calculating of the various bridge span constructions which take the thin plate as the mechanics model.