摘要
针对现有锚具“切口效应”及夹持应力分布不均而易导致CFRP板损伤的问题,该文提出了一种新型夹片外伸式CFRP板锚具。该设计利用钢材的延性进行应力扩散,引导CFRP板内的压应力区向远离切口端移动,实现了CFRP板在夹片端口处的夹持力平缓过渡,有效降低“切口效应”;同时,该设计减小了碳纤维间的应变差,使CFRP板的横向变形更同步,降低了发生劈裂破坏的风险。该文针对新型锚具及目前常用的夹片内缩锚具、角度差锚具开展对比研究,通过有限元建模分析以及静载张拉试验,分析新型锚固系统在不同设计变量下的传力机理,优化设计参数。结果表明:夹片内缩的常规锚具破坏形式为CFRP板切口破坏,锚固效率仅为60.42%;角度差设计导致CFRP板横截面上压应力梯度过大,产生不同步的张拉应变,破坏形式为先劈裂后拉碎,锚固效率不足80%;夹片外伸式CFRP板锚具锚固效率高达90.83%,有效解决了CFRP板“切口效应”及劈裂破坏风险,具有很高的工程应用价值。
Existing anchorage is prone to damaging the carbon-fiber reinforced polymer(CFRP)plate due to the“notch effect”and uneven distribution of clamping stress.This study proposed a new clip-extension type anchorage for the CFRP plate.This design utilized the ductility of steel for stress diffusion and guided the compressive stress zone in the CFRP plate away from the notched end,realizing a smooth transition of the clamping force of the CFRP plate at the clip port and effectively reducing the“notch effect”.The design also reduced the strain difference between the carbon fibers,resulting in a more synchronized lateral deformation of the CFRP plate and reducing the risk of splitting damage.A comparative study of new anchorages,commonly used clip-inward retraction anchorages,and angle difference anchorages was conducted.Through finite element modeling analysis and static load tensioning test,the force transmission mechanism of the new anchorage system under different design variables was analyzed,and the design parameters were optimized.The results show that the conventional anchorage damage in the form of CFRP plate notch damage for clip-inward retraction has an anchoring efficiency of only 60.42%.The angular difference design leads to excessive compressive stress gradient on the cross-section of the CFRP plate,which produces asynchronous tension strain.The damage form is split first and then tensile shattering,and the anchoring efficiency is less than 80%.The anchoring efficiency of the clip-extension type anchorage for the CFRP plate is as high as 90.83%,which effectively avoids the“notch effect”and splitting damage,and has high practical application value in engineering.
作者
齐艺佳
肖丹
王中强
QI Yijia;XIAO Dan;WANG Zhongqiang(School of Civil and Environmental Engineering,Changsha University of Science&Technology,Changsha,Hunan 410114,China)
出处
《中外公路》
2025年第6期189-198,共10页
Journal of China & Foreign Highway
基金
湖南省教育厅科学研究项目(编号:23A0248)
先进工程材料与结构力学行为及智能控制湖南省高校重点实验室开放基金项目(编号:13KA05)
长沙理工大学桥梁工程领域开放基金项目(编号:11KA14)
长沙理工大学桥梁与隧道工程创新性项目(编号:11ZDXK02)
长沙理工大学土木工程重点学科创新性项目(编号:13ZDXK08)。
关键词
桥梁工程
CFRP板锚具
夹片式锚具
有限元模拟
静载试验
锚固性能
切口效应
劈裂破坏
bridge engineering
CFRP plate anchorage
clip anchorage
finite element simulation
static load test
anchoring performance
notch effect
splitting damage
