预应力CFRP板平板锚具承载力评估理论与试验研究
PDF下载 (346)储焙宇,钱登朝,诸葛萍,杨科龙.预应力CFRP板平板锚具承载力评估理论与试验研究[J].宁波大学学报(理工版),2020,33(4):41-48.DOI:
CHU Beiyu,QIAN Dengchao,ZHUGE Ping,YANG Kelong.Theoretical and experimental study on load-carrying capacity evaluation of CFRP plates bond-type anchors[J].Journal of Ningbo University(Natural Science & Engineering Edition),2020,33(4):41-48.DOI:
| Title: | Theoretical and experimental study on load-carrying capacity evaluation of CFRP plates bond-type anchors |
| 作者: | 储焙宇, 钱登朝, 诸葛萍, 杨科龙 |
| Author(s): | CHU Beiyu, QIAN Dengchao, ZHUGE Ping, YANG Kelong |
| 关键词: | 桥梁工程; CFRP板; 平板锚具; 界面剪应力; 承载力 |
| Keywords: | bridge engineering; CFRP plates; bond-type anchor; interfacial shear stress; load-carrying capacity |
| 分类号: | U444 |
| 文献标识码: | A |
| 摘要: | 为揭示CFRP板平板锚具的锚固机理, 建立了该锚具的承载力理论模型, 并利用该模型预测CFRP板平板锚具的临界锚固长度. 通过试验获得了模型所需的锚固界面剪应力与压应力的关系式. 该模型研究了锚固区界面剪应力的纵向折减及横向压应力分布的不均匀性, 并通过试验测得了界面剪应力的纵向折减系数. 利用上述模型就平板锚具设计参数对锚固性能的影响进行了分析. 结果表明, 界面剪应力折减率随着锚固长度的增大而增大, 横向压应力分布的不均匀性随着锚固宽度的增大而增大, 增大界面压应力和夹板厚度能有效提高横向压应力分布的均匀度; 临界锚固长度随夹板厚度的增大而减小, 且当夹板达到合适厚度后继续增大, 对临界锚固长度的影响逐渐变小; 随着界面压应力的增大, 界面剪应力增大, 临界锚固长度减小; 对于工程常用CFRP板尺寸100mm×2.0mm, 当界面压应力取100MPa, 平板锚具夹板厚度取32mm时, 所需的临界锚固长度为296mm, 对应的锚具设计承载力为480kN, 理论上能使CFRP板抗拉强度获充分发挥. |
| Abstract: | In order to reveal the anchoring mechanism of CFRP plate anchorage, a theoretical model of the carrying capacity was developed, and the model can be used to predict the critical anchorage length of CFRP plate anchorage. The relationship between shear stress and compressive stress on anchorage interface was obtained by experiments. The longitudinal reduction of shear stress and the ununiformity of transverse compressive stress of the anchorage zone were investigated in the model, and the longitudinal reduction coefficient of the interfacial shear stress was measured by experiments. Using the above model, the influence of the design parameters of anchorage system on anchorage performance was analyzed. The results show that the reduction rate of interfacial shear stress increases with the increase in anchorage length. The ununiformity of the transverse compressive stress distribution increases with the increase in anchorage width. By increasing the interfacial compressive stress and the thickness of splint, it can effectively improve the uniformity of the transverse compressive stress distribution. The critical anchorage length decreases with the increase of the splint thickness, and when the splint reaches the appropriate thickness, the influence on the critical anchorage length decreases gradually. With the increase of interfacial compressive stress, however, the interfacial shear stress shall increase and the critical anchorage length shall decrease. When the interfacial pressure stress is less than 100MPa, it has a linear relationship with the interfacial shear stress. For the commonly used CFRP plate size 100mm×2.0mm in engineering, when the interfacial compressive stress is 100MPa and the splint thickness of plate anchorage is 32mm, the required critical anchorage length is 296mm, and the corresponding anchorage design bearing capacity is 480kN, which can give full play to the tensile strength of CFRP plate theoretically. |
| 参考文献 /References: | [1] 叶列平, 冯鹏. FRP在工程结构中的应用与发展[J]. 土木工程学报, 2006, 39(3):24-36. [2] Reda M M, Sayed-Ahmed E Y, Shrive N G. Towards a new non-metallic anchorage system for post-tensioned applications with carbon fiber reinforced plastic tendons[C]. 42nd International SAMPE Symposium, Anaheim, USA, 1994:288-297. [3] 潘勇, 夏叶飞, 张红雷, 等. 预应力CFRP板在公路桥梁加固中的应用[J]. 中外公路, 2017(2):116-120. [4] Motavalli M, Czaderski C, Pfyl-Lang K. Prestressed CFRP for strengthening of reinforced concrete structures: Recent developments at Empa, Switzerland[J]. Journal of Composites for Construction, 2011, 15(2):194-205. [5] El-Hacha R, Gaafar M. Flexural strengthening of reinforced concrete beams using prestressed, near-surface-mounted CFRP bars[J]. PCI Journal, 2011, 56(4):134-151. [6] Ali A, Abdalla J, Hawileh R, et al. CFRP mechanical anchorage for externally strengthened RC beams under flexure[J]. Physics Procedia, 2014, 55:10-16. [7] Garden H N, Hollaway L C. An experimental study of the failure modes of reinforced concrete beams strengthened with prestressed carbon composite plates[J]. Composites Part B Engineering, 1998, 29(4):411-424. [8] Andr? H P, Maier M. Post-strengthening with externally bonded prestressed CFRP strips[J]. IABSE Congress Report, 2000, 16(7):1507-1514. [9] Burtscher S L. Wedge anchorage for CFRP strips[J]. Journal of Composites for Construction, 2008, 12(4):446-453. [10] Kim Y J, Wight R G, Green M F. Flexural strengthening of RC beams with prestressed CFRP sheets: Development of nonmetallic anchor systems[J]. Journal of Composites for Construction, 2008, 12(1):35-43. [11] 薛伟辰, 曾磊, 谭园. 预应力CFRP板加固混凝土梁设计理论研究[J]. 建筑结构学报, 2008, 29(4):127-133. [12] 尚守平, 彭辉, 张毛心, 等. 土木建筑工程用的碳纤维板锚具: 200610031436.2[P]. 2006-09-06. [13] 邓朗妮, 姬帅, 张鹏, 等. 预应力碳纤维板夹片式锚具设计与试验研究[J]. 建筑结构, 2014, 44(11):73-76. [14] 卓静, 李唐宁, 邢世建, 等. 一种锚固FRP片材的体外预应力新方法[J]. 土木工程学报, 2007, 40(1):15-19. [15] 吴志平, 俞志杰, 娄亮, 等. 预应力碳纤维板平板锚具锚固性能试验[J]. 沈阳建筑大学学报(自然科学版), 2013, 29(2):251-256. [16] JSCE-E531-1995. Test method for tensile properties of continuous fiber reinforcing materials[S]. |
| 备注/Memo: | 收稿日期: 2019－10－14. 宁波大学学报（理工版）网址: http://journallg.nbu.edu.cn/基金项目: 浙江省公路与运输管理中心科技计划（2019H18）; 国家山区公路工程技术研究中心开放基金（GSGZJ-2019-04）.第一作者: 储焙宇（1994－）, 男, 浙江宁海人, 在读硕士研究生, 主要研究方向: 桥梁工程. E-mail: 501454974@qq.com*通信作者: 诸葛萍（1982－）, 男, 浙江瑞安人, 副教授, 主要研究方向: 桥梁工程. E-mail: zhugeping@nbu.edu.cn 宁波大学学报（理工版）网址：http://journallg.nbu.edu.cn/ |
