·The effective shear-span/depth ratio(广义剪跨比)is defined as M/Th,where M is the bending moment and V the shear force.This is true for both distributed loading or concentrated loading. The failure mode is strongly dependent on the shear-span/depth ratio a./ho Why? 广义剪跨比实质上反映了截面上正应力与剪应力之间的相对关系， 近而决定了主应力的大小和方向，也就影响了斜截面受剪承载力和 破坏形态。 The shear-span/depth ratio can be divided into four general categories.For different members falling into the same category, the sequence of events and the nature of the failure are approximately the same.• The effective shear-span/depth ratio (广义剪跨比）is defined as , where M is the bending moment and V the shear force. This is true for both distributed loading or concentrated loading. M /Vh0 • The failure mode is strongly dependent on the shear-span/depth ratio a / h0 v The shear-span/depth ratio can be divided into four general categories. For different members falling into the same category, the sequence of events and the nature of the failure are approximately the same. Why? 广义剪跨比实质上反映了截面上正应力与剪应力之间的相对关系， 近而决定了主应力的大小和方向，也就影响了斜截面受剪承载力和 破坏形态