带预应力UHPC华夫桥面板抗弯性能试验研究
Experimental Study on Flexural Performance of Prestressed UHPC Waffle Deck Panels
李晓龙 1陈晖 1王泽辉 2袁泉 2王巍3
作者信息
- 1. 北京市市政工程设计研究总院有限公司,北京 100082
- 2. 北京交通大学土木建筑工程学院,北京 100044;结构风工程与城市风环境北京市重点实验室,北京 100044
- 3. 深圳中冶南方城建工程技术有限公司,广东深圳 518028
- 折叠
摘要
为研究钢纤维类型、预应力筋等因素对UHPC华夫桥面板力学性能的影响,以北京亦庄文昌桥为背景进行抗弯试验研究.设计制作了 4组板肋梁试件,对比分析钢纤维类型(直线型、端钩型)、预应力筋等因素对试件破坏模式、裂缝发展以及抗弯承载力等性能的影响,并基于美国《UHPC华夫板设计指南》,提出考虑预应力筋的华夫桥面板抗弯承载力计算公式.结果表明:底部纵向受拉筋的屈服是试件进入破坏阶段的特征之一,试件最终为适筋梁受弯破坏;设置预应力筋能一定程度提升试件的强度和延性,并能有效增加初裂缝附近UHPC的应变;设置预应力筋能明显改善试件的耐久性,而且钢纤维为直线型时提升效果比端钩型更显著;提出的抗弯承载力计算值与试验值吻合较好,能准确计算UHPC华夫桥面板的抗弯承载力.
Abstract
This paper studies the factors influencing the mechanical properties of the UHPC waffle deck panels,with the focuses on the types of the steel fibers and prestressing tendons.Based on the Wenchang Bridge located in Yizhuang,Beijing,four groups of rib-stiffened plate girder specimens were prepared for flexural tests.The effects of the types of steel fibers(straight and end-hooked fibers)and prestressing tendons on the failure modes,cracking propagation and flexural strengths of specimens were analyzed.Referencing the American Design Guide for Precast UHPC Waffle Deck Panel System,Including Connections,the formulas to calculate the flexural strength of the waffle deck panels with prestressing tendons were proposed.The results demonstrate that the yielding of the longitudinal tensile tendons in the bottoms of the waffle panels signals the onset of specimen failure,and the damage is finally designated as the flexural failure of the prestressed waffle panels.Adding prestressing tendons can enhance the strength and ductility of specimens to a degree,and effectively increase the strain of UHPC near the initial cracks.Adding prestressing tendons can significantly improve the durability of the specimens,and the improvement is more distinct when using end-hooked steel fibers,compared to straight steel fibers.The calculated flexural strengths agree well with the test data,proving the efficiency of the proposed formulas in calculating flexural strength of the UHPC waffle panels.
关键词
UHPC华夫桥面板/钢纤维/预应力/抗弯能力/裂缝发展模式/抗弯承载力计算公式/抗弯试验Key words
UHPC waffle panel/steel fiber/prestress/flexural capacity/cracking propagation mode/flexural strength calculation formula/flexural test引用本文复制引用
出版年
2024
NETL
NSTL
万方数据