Experimental Study on a New Clamping Anchor for Carbon Fiber Reinforced Polymer Plate
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摘要:
针对传统碳纤维增强复合材料(CFRP)板锚具压应力沿横向分布不均匀,导致张拉过程中板材易发生撕裂破坏的问题,研制了一种CFRP板新型夹持式锚具. 新型锚具在中轴线上布置预压螺栓,同时设定螺栓长度,通过控制螺栓的位移量对CFRP板施加定量的压紧力,分析新型锚具的受力机理;使用有限元软件ANSYS进行模拟,分析影响锚固性能的关键因素;对厚度为2 mm、宽度为50 mm的CFRP板进行静载张拉试验. 研究结果表明:1) 新型锚具的锚固性能与夹片厚度、外夹板厚度及螺栓预紧力密切相关;当夹片厚度为20 mm时,横向上CFRP板的压应力分布较均匀,最大与最小压应力之差仅为9.8 MPa;当上、下外夹板的厚度分别为30 mm和20 mm时,各构件的弯曲应力均保持在安全范围内;当螺栓预紧力为170 kN时,CFRP板的压应力水平显著提高,而剪切应力始终处于较低水平. 2) 在静载张拉试验中,新型锚具承受的最大张拉力为260.7 kN,锚固效率达到了108.63%;CFRP板的破坏形式为炸丝破坏,未出现撕裂等异常破坏形式,锚具的静载锚固性能优异.
Abstract:To address the problem of uneven transverse compressive stress distribution in traditional carbon fiber reinforced polymer (CFRP) plate anchors, which makes the plate prone to tearing failure during the tensioning process, a new clamping anchor for CFRP plates was developed. The new anchor features a preloaded bolt arranged along the central axis. By setting the bolt length and controlling its displacement, a quantified compressive force was applied to the CFRP plate, and the force mechanism of the new anchor was analyzed. Next, finite element software ANSYS was used for simulation, and the key factors affecting anchorage performance were analyzed. Finally, a static tensile test was performed on a CFRP plate with a thickness of 2 mm and a width of 50 mm. The results are as follows. 1) The anchorage performance of the new anchor is closely related to the clamp thickness, the outer clamp plate thicknesses, and the bolt preload force. When the clamp thickness is 20 mm, the transverse compressive stress distribution of the CFRP plate is relatively uniform, with a difference between the maximum and minimum compressive stresses of only 9.8 MPa. When the thicknesses of the upper and lower outer clamp plates are 30 mm and 20 mm, respectively, the bending stress of each component remains within a safe range. When the preload force of the bolt is 170 kN, the compressive stress level in the CFRP plate significantly increases, while the shear stress remains consistently low. 2) In the static tensile test, the new anchor withstands a maximum tensile force of 260.7 kN, achieving an anchoring efficiency of 108.63%. The failure mode of the CFRP plate is fiber rupture, with no tearing or other abnormal failure modes observed. The anchor demonstrates excellent static anchorage performance.
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表 1 锚具各部件主要设计参数
Table 1. Main design parameters of anchor components
部件 设计参数/mm CFRP板 横截面尺寸:厚/宽 2/50 上夹板 长/宽/厚 180/110/30 下夹板 整体尺寸:长/宽/厚 180/110/42 凹槽宽度 50 底部厚度 20 夹片 长/宽/厚 180/50/20 圆槽厚度 3 表 2 CFRP板材料性能
Table 2. Material properties of CFRP plate
CFRP尺寸(厚度、
宽度)/mm极限抗拉
强度/MPa极限承
载力/kN弹性模量
/GPa极限延
伸率/%2、50 2400 240 160 1.5 表 3 钢材材料性能
Table 3. Material properties of steel
材质 抗拉强度
/MPa屈服强度
/MPa弹性模量
/GPa泊松比 Q355B 600 355 206 0.32 表 4 螺栓材料性能
Table 4. Material properties of bolt
螺栓等级 公称直径
/mm抗拉强度
/MPa屈服强度
/MPa屈强比 12.9 20 1200 1080 0.9 表 5 静载张拉试验结果汇总
Table 5. Summary of static load tension test results
试件
编号理论最大
承载力/kN实际最大
承载力/kN锚固
效率/%CFRP板最终
破坏形式S1 240 213.22 88.84 先劈裂后拉碎 S2 240 218.37 90.99 先劈裂后拉碎 S3 240 207.65 86.52 先劈裂后拉碎 S4 240 246.90 102.88 炸丝破坏 S5 240 260.70 108.63 炸丝破坏 S6 240 240.63 100.26 炸丝破坏 S7 240 249.38 103.91 炸丝破坏 S8 240 242.53 101.05 炸丝破坏 -
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