CFRP筋粘结式楔型锚具锚固性能分析

Analysis of anchorage performance of a bond-type anchor for CFRP tendon

为研究CFRP筋粘结式楔型锚具锚固性能及其影响因素,对12套CFRP筋粘结式楔型锚具进行静载试验,以锚具内倾角和锚固长度为变化参数,获取锚具试件荷载—滑移全过程曲线,推出锚具内部CFRP筋与环氧树脂砂浆界面粘结—滑移本构模型。研究表明:增大锚具内倾角和锚固长度可提高锚具极限荷载,平均粘结强度随锚具内倾角的增大呈增大趋势,临界锚固长度随试件锚具内倾角的增大呈减小趋势,采用回归公式计算的平均粘结强度值与试验实测值比较接近;锚固长度是影响界面粘结剪切刚度的主要因素;锚固长度和锚具内倾角可一定程度提高界面抗滑移能力,损伤发展后期,锚固长度越大,损伤速率越慢;推导出的锚具内CFRP筋与环氧树脂砂浆的粘结—滑移本构关系模型适用性较好。

For the study of the anchoring performance and influencing factors of bond anchor for CFRP tendons,12 sets of bond anchors for CFRP tendons were designed for static load test.Two test parameters of internal inclination of anchorage and anchorage length were considered to study their influences on the load-slip behaviors of bond anchor for CFRP tendons.Load-slip curve and the bond-slip constitutive model between CFRP tendons and epoxy resin mortar were obtained.The results show that the ultimate load of the anchorage can be increased by increasing the internal inclination of anchorage and anchorage length.The average bond strength increases with the increase of the internal inclination of anchorage,and the critical anchorage length decreases with the increase of the internal inclination of anchorage.The value of average bond strength calculated by regression formula is similar to the experiment value.Increasing the anchorage length is beneficial to the bonding shear stiffness of the interface.Anchorage length and internal inclination of anchorage can improve the anti-slip capacities of the interface.In the later stage of damage,the anchorage length increase as the damage rate decrease.The bond-slip constitutive model between CFRP tendons and epoxy resin mortar in anchorage agree with the experimental results.