玻璃纤维增强聚合物抗浮锚杆的临界锚固长度计算

考虑到抗浮锚杆的工作机理与抗拔桩相似的特性,基于理想同心薄壁圆柱体剪切模型及抗浮锚杆剪应力分布简化模型,推导出GFRP抗浮锚杆的临界锚固长度的解析式,并以工程实例检验该方法的合理性。研究结果表明：本文提出的GFRP抗浮锚杆临界锚固长度解析计算方法是可行的,将理论临界锚固长度的2/3作为GFRP抗浮锚杆实际锚固长度参考值,可以在保证承载性能的前提下提高材料利用率。GFRP抗浮锚杆临界锚固长度理论值随锚杆杆体-岩土体弹性模量比值的增大而增大,但在该比例逐渐变大的过程中,临界锚固长度增长幅度逐渐降低。此外,增加杆体半径亦可提高理论临界锚固长度。研究结果可为GFRP抗浮锚杆的推广使用提供理论依据与实践参考。

Calculation for the critical anchorage length of GFRP anti-floating anchor

Considering the comparability for the working mechanism of anti-floating anchor and uplift pile, we deduced the analytical function for critical anchorage length of GFRP anti-floating anchor based on the concentric thin-walled cylinder shear model and simplified shear stress distributional model of the anti-floating anchor. The rationality of the method mentioned above was also examined in some engineering projects. The results show that the analytical method for calculating the critical anchorage length of GFRP anti-floating anchor is feasible in this paper, and 2/3 of the theoretical critical anchorage length is taken as the reference value of the actual anchorage length of GFRP floating anchor, which can improve the material utilization and guarantee the bearing capacity at the same time. The theoretical critical anchorage length of GFRP anti-floating anchor will increase with the increase of the elasticity modulus ratio of the anchor bolt and rock-soil mass. During the process of the promotion of the ratio, the increased amplitude of the critical anchorage length will reduce gradually. Additionally, the theoretical critical anchorage length will also increase with the increase of the anchor bolt radius. The research results could provide the theoretical foundation and practice reference for the application of GFRP anti-floating anchor.