Shear Strength Formula for RC Beams with Stirrups Based on Distinct Failure Mechanism in Rezoned Compression Zone

被引：0
|
作者：
Zheng K.-Q. [1 ,2 ,3 ]
Liu Z. [2 ]
机构：
[1] College of Civil Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu
[2] Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education, Southeast University, Nanjing, 210096, Jiangsu
[3] National-provincial Joint Engineering Research Center of Electromechanical Product Packaging, Nanjing, 210037, Jiangsu
来源：
Zhongguo Gonglu Xuebao/China Journal of Highway and Transport | 2020年 / 33卷 / 01期
关键词：
Bridge engineering; Compression zone; Distinct failure; Reinforced concrete beam; Shear capacity; Shear model;
D O I：
10.19721/j.cnki.1001-7372.2020.01.008
中图分类号：
学科分类号：
摘要：
Because of the complexity of transfer mechanisms and the diversity of shear failure modes of reinforced concrete (RC) beams, the accuracy of current shear capacity equations fluctuates obviously with variations in shear parameters, and the scope of these equations is limited. Based on the distinct failure mechanism in concrete compression zone (CCZ), a modified formula for the height of CCZ was proposed in this study from the perspective of preventing early yielding of longitudinal reinforcement, and the concrete shear expression compatible with both low- and high-strength RC beams is obtained. Second, through the rotation law of diagonal crack angle, different stages of the cooperative working mechanism between concrete and stirrups were analyzed, and the calculation principle of the shear contribution of stirrups was proposed. Furthermore, the shear capacity formula of RC beams with web reinforcement based on rezoned compression zone was established. The sub-items of the formula directly reflect the shear contribution of three parts, namely, the shear compression zone, diagonal tension zone, and stirrups. In addition, the formula reflects the influences of the main shear parameters such as concrete strength, longitudinal reinforcement ratio, stirrup ratio, shear span to depth ratio, and size effect. Finally, based on a shear database, the proposed and current commonly used formulas were verified, and the prediction accuracy and parameter sensitivity of each formula were compared and evaluated. The results show that the adopted distinct failure mechanism in CCZ can reflect the evolution of shear failure modes with shear span ratio. The proposed shear capacity formula has higher accuracy and stability, is less sensitive to a wide range of changes in shear parameters, and has better applicability to high-strength and large-size specimens. © 2020, Editorial Department of China Journal of Highway and Transport. All right reserved.
引用
收藏
页码：79 / 86and110
相关论文
共 24 条
  • [1] Ollins M.P., Kuchma D., How Safe are Our Large, Lightly Reinforced Concrete Beams, Slabs, and Footings, ACI Structural Journal, 96, 4, pp. 482-490, (1999)
  • [2] Yu L., Che Y., Song Y.-P., Experimental Study on Shear Strength of Large-size Reinforced Concrete Beams Without Web Reinforcement, China Civil Engineering Journal, 46, 1, pp. 1-7, (2013)
  • [3] GB50010-2010, Code for Design of Concrete Structures
  • [4] ACI 318M-14, Building Code Requirements for Structural Concrete and Commentary
  • [5] Thurlimann B., Plastic Analysis of Reinforced Concrete Beams, IABSE Colloquium on Plasticity in Reinforced Concrete, pp. 71-90, (1979)
  • [6] Nielsen M.P., Hoang L.C., Limit Analysis and Concrete Plasticity, (2010)
  • [7] EN 1992-1-1, Eurocode 2: Design of Concrete Structures: Part 1-1: General Rules and Rules for Buildings
  • [8] Vecchio F.J., Collins M.P., The Modified Compression-field Theory for Reinforced Concrete Elements Subjected to Shear, ACI Structural Journal, 83, 2, pp. 219-231, (1986)
  • [9] AASHTO LRFD US-6, AASHTO LRFD Bridge Design Specifications (6th ed)
  • [10] CSA A23.3-04, Design of Concrete Structures
123