短期荷载作用下钢-竹界面黏结应力和滑移分析

为研究钢-竹界面黏结应力与滑移分布，设计了两种类型的界面：型钢与竹板仅通过胶黏剂粘贴的单纯胶结型界面以及在胶黏剂粘贴基础上用螺钉加强的复合胶结型界面，并进行6个钢-竹组合试件的推出试验，得到黏结界面的剪切承载力及外贴竹板的应变。通过力学分析推导出外贴竹板正应力二阶微分方程，结合边界条件与数据拟合解得外贴竹板正应力表达式，并建立了钢-竹界面剪应力与相对滑移计算式，在此基础上提出了短期荷载作用下的钢 竹界面承载力计算方法。试验与理论分析结果表明：钢-竹界面剪切黏结性能良好，复合胶结型界面试件的破坏具有显著的延性特征；外贴竹板正应力试验值与拟合值吻合度高，以此为基础计算剪应力与相对滑移较为可靠；钢-竹界面剪应力与相对滑移分布具有两端大中间小的特征，且竹板受力端黏结界面的剪应力和滑移量明显大于黏结基体受力端黏结界面，剪应力最大值约为1.64 MPa；钢-竹界面剪切黏结承载力计算值与试验值吻合较好，其计算误差小于8%。

Study on bond stress and bond slip of bamboo-steel interface under static load

In order to investigate the distribution of bamboo-steel interfacial bonding stress and bond-slip, two kinds of interfaces were designed: the pure bonding interface which combines bamboo and steel with structural adhesive and the composite bonding interface which combines interfaces with adhesive and self-tapping screws. Six specimens were made to perform the push-out test, in which the bearing capacities and strain data of the bamboo plate were acquired. Based on mechanical analyses, a second order differential equation of the distribution of normal stress of bamboo plate was derived. Analytical solution for the equation was acquired through boundary conditions and data fitting, and formulas to calculate the interfacial shear stress and bond-slip were established afterwards. Furthermore, expressions about the bearing capacity for bamboo-steel interfaces under static load were developed on basis of shear stress formula. Experimental and analytical results show that the bamboo-steel interfaces own excellent performances; the damage of the composite-interface-specimen-has-significant-ductility-characteristics. Experimental values of the bamboo plate’s normal stress agree well with the fitted values, which provides a solid reference to calculation of the interfacial shear stress and slip. The distribution of interfacial shear stress and slip has a characteristic that the maximum values occur at the boundary side while the minimum values are found in middle part of the interface. The interfacial shear stress and slip near the pressure point of the bamboo plate are obviously greater, when compared with those near the pressure point of the adhesive substrate, and the maximum value of the shear stress is approximately 1.64 MPa. The calculated values of bearing capacity agree well with experimental values with the calculation deviation less than 8%.