采用ANSYS 有限元与试验相结合的方法，研究了板件截面抗弯承载力与抗剪承载力随剪跨比变化的趋势，分析了在跨中单点( 两点对称) 加载下剪跨比对板件破坏模式的影响规律．结果表明: 钢板剥离破坏仅发生在抗剪连接件不完全剪力连接时的板件; 在跨中单点( 两点对称) 加载下，剪跨比小于7.5( 7) 时，截面抗弯承载力较抗剪承载力充足，试件发生剪切破坏; 剪跨比在7.5( 7) 与10( 9) 之间时，截面抗弯与抗剪承载力均不足，试件发生弯剪破坏; 剪跨比大于10( 9) 时，截面抗弯承载力较抗剪承载力不足，试件发生弯曲破坏．

By combining the ANSYS-based finite element method with the test, the changes of the flexural bearing capacity and shear bearing capacity of specimens with the shear-span ratio are analyzed, and the influence of the shear-span ratio on the failure mode of specimens is investigated respectively under single-point and two-point symmetric loading on the midspan. The results show that (1) the debonding failure of steel plates occurs only when the shear connection are not complete; (2) under the single-point ( two-point symmetric) loading on the midspan with a shear-span ratio of less than 7.5 (7) , the flexural bearing capacity of section is more sufficient than the shear bearing capacity, so the shear failure of specimens occurs; (3) when the shear span ratio is between 7.5(7) and 10(9) , neither the flexural bearing capacity of section nor the shear bearing capacity is sufficient, so the bending shear failure of specimens occurs; and (4) when the shear span ratio is more than 10(9) , the flexural bearing capacity of section is more insufficient than the shear bearing capacity, so the bending failure of specimens occurs.