+高级检索
负弯矩作用下UHPC湿接缝桥面板裂后性能研究
DOI:
作者:
作者单位:

作者简介:

通讯作者:

基金项目:


Research on Post-cracking Behavior of UHPC Wet Joint Bridge Panels under Negative Bending Moment
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
    摘要:

    针对预制拼装桥面板接缝处受力复杂、易开裂等问题,提出了一种新型超高性能混凝土(Ultra-high Performance Concrete, UHPC)燕尾榫接缝.通过负弯矩作用下荷载模型试验,研究了不同接缝材料和预应力水平对UHPC湿接缝桥面板极限承载力、破坏形式及裂缝分布等的影响规律.基于试验验证的数值仿真模型,对比分析了不同接缝位置、接缝形式、纵筋率、材料强度及板件厚度等参数对湿接缝受弯性能的影响.研究结果表明:预应力由0 MPa提高到5 MPa,板件开裂应力和极限承载力分别提升40.0%和5.5%;燕尾榫接缝较直角榫接缝与平接缝的开裂应力分别提高7.5%和16.0%,承载力分别提高5.4%和16.0%.燕尾榫接缝整体性好,改变接缝位置对湿接缝受弯性能影响较小;板件开裂应力和极限承载力随材料强度增大而提高,材料强度超过120 MPa时增幅减小;UHPC接缝初裂刚度约为初始刚度的90%,剩余刚度约为初始刚度的25%;初裂后,结构刚度迅速下降,纵筋屈服后,结构刚度退化速度明显减缓,最终刚度保持在剩余刚度;提出了用极限荷载对应位移与开裂荷载对应位移之比为表达形式的UHPC湿接缝桥面板裂后延性系数,本文板件裂后延性系数为10.0~20.0,表明UHPC湿接缝桥面板具有较好的裂后变形能力.

    Abstract:

    Aiming at the problems of complex force and easy cracking at the joints of prefabricated assembled bridge decks, a new type of ultra-high performance concrete (UHPC) dovetail joints was proposed. Through the load model test under the action of negative bending moment, the influence of different joint materials and prestress levels on the ultimate bearing capacity, failure form and crack distribution of UHPC wet joint bridge panels were studied. Based on the numerical simulation model verified by the experiment, the influence of different joint positions, joint forms, longitudinal reinforcement ratio, material strength, and thickness of the specimens on the bending performance of wet joints were compared and analyzed. The results showed that when the prestress was increased from 0 MPa to 5 MPa, the cracking stress and ultimate bearing capacity of the specimen were increased by 40.0% and 5.5%, respectively; The cracking stress of the dovetail joints was increased by 7.5% and 16.0%, respectively, and the bearing capacity was increased by 5.4% and 16.0%, respectively, when compared with the right angle joints and flat joints. Integrity of dovetail joints was good, and changing the joint position had little impact on the bending performance of the wet joint; The cracking stress and ultimate bearing capacity of the specimen increased with the increase of material strength, and the growth rate decreased when the material strength exceeds 120 MPa; The initial cracking stiffness of UHPC joints was about 90% of the initial stiffness, and the residual stiffness was about 25%; After the appearance of the first crack, the structural stiffness decreased rapidly, and after the longitudinal reinforcement yielded, the structural stiffness degradation rate was significantly slowed down, and the final stiffness remained at the residual stiffness; The ratio of the corresponding displacement of the ultimate load to the displacement of the cracking load was proposed as the expression form of UHPC wet joint bridge panels cracking ductility coefficient, and the results of crack ductility coefficient was 10.0~20.0, indicating that the post-cracking deformation ability of UHPC wet joint bridge panels was better.

    参考文献
    相似文献
    引证文献
文章指标
  • PDF下载次数:
  • HTML阅读次数:
  • 摘要点击次数:
  • 引用次数:
引用本文

戚家南 ?,程杭 ,邹伟豪 ,王景全 .负弯矩作用下UHPC湿接缝桥面板裂后性能研究[J].湖南大学学报:自然科学版,2022,49(11):57~66

复制
历史
  • 收稿日期:
  • 最后修改日期:
  • 录用日期:
  • 在线发布日期: 2022-12-12
  • 出版日期:
作者稿件一经被我刊录用,如无特别声明,即视作同意授予我刊论文整体的全部复制传播的权利,包括但不限于复制权、发行权、信息网络传播权、广播权、表演权、翻译权、汇编权、改编权等著作使用权转让给我刊,我刊有权根据工作需要,允许合作的数据库、新媒体平台及其他数字平台进行数字传播和国际传播等。特此声明。
关闭