计及跨中界面破坏的碳纤维板加固砼梁四点弯曲破坏分析

借鉴复合材料力学，建立一种计及跨中界面破坏的分层剪滞模型，并结合能量破坏准则，研究了含裂缝的碳纤维板加固素砼梁和钢筋砼梁在四点弯曲荷载作用下的应力重新分布和极限承载力，首次定量获得了碳纤维板与砼梁之间的界面破坏区长度和极限承载力与界面剪切强度的关系．结果表明：界面破坏区长度随界面剪切强度和碳纤维粘贴层数的增加而减小；极限承载力随碳纤维粘贴层数的增加而增加，随界面剪切强度的增加是先增大后减小；适宜的界面黏结，极限承载力最高．

Four-point Bending Failure Analysis of Carbon Fiber Sheet-reinforced Concrete Beams Accounting for Interfacial Failure in Mid-span

Using the analytical methods of composite mechanics for reference, this paper established a layering shear-lag model accounting for the interfacial failure in mid-span and incorporated an energy failure criterion to study the stress redistributions and failure loads of carbon fiber sheet-reinforced concrete and reinforced concrete beams with a crack under 4-point bending. The variation of both the lengths of interfacial damage area between carbon fiber sheet and concrete and the failure loads as a function of the interfacial shear strength was first obtained quantitatively. The results show that the length of interfacial damage area is reduced as the increase of the interfacial shear strength and the number of carbon fiber sheets. The failure load is increased as the increase of the number of carbon fiber sheets and first increased and then decreased as the increase of the interfacial shear strength. Obviously, the failure load of members is highest if an interfacial cohesion is suitable.