贴片加固混凝土梁界面粘结剪应力的分析与计算

以弹性理论为基础,根据贴片加固混凝土梁的截面变形协调条件和静力平衡条件,推导出了任意线性荷载作用下贴片加固梁的界面粘结剪应力及片材端部界面最大粘结剪应力的计算公式,并给出了均布荷载和集中荷载2种情况下的具体表达式.研究结果表明:由于表达式考虑了混凝土梁、粘结胶层和加固片材性能对界面粘结剪应力的影响,因而具有更高的计算精度;采用这些公式可以对不同荷载作用、不同粘结长度和宽度及不同梁截面形式的贴片加固梁片材端部界面最大粘结剪应力进行验算,以防止加固梁片材端部出现界面剥离破坏.

Analysis and Calculation of Interfacial Bonding Shear Stress of Reinforced Concrete Beams Strengthened with Plates

Based on the linear elastic theory, a new analytical solution is developed for a plate strengthened reinforced concrete beam under a linear distributed load using the cross sectional equilibrium and compatible conditions. The interfacial shear stress distribution along the bond line and its maximum value at the cut off point of the plate were given. And direct analytical ex pressions were presented for the cases of concentrated loading as well as uniform loading. The comparative results show that the present solution has better accuracy because the influences of the behaviors of reinforced concrete beam, adhesive and strengthening plate on the interfacial shear stress are all considered. For a plate strengthened reinforced concrete beam under different loading,plate length and width and different cross section, the solution can be used to check the maximum bonding shear stress to prevent the plate debonding in the beam at the cut off point of the plate.