Experimental Research on Damage Characteristics of Stirrup-Confined Concrete Under Uniaxial Compression
-
摘要: 针对箍筋约束混凝土的损伤特性,设计了多组试验,通过单轴受压试验,对比分析了加载速率、混凝土强度、箍筋直径、体积配箍率等因素对约束混凝土试块力学性能和损伤特性的影响。通过试验结果表明:1)随着加载速率的增加,混凝土试块弹性变形阶段缩短,整个损伤过程塑性减弱,脆性增强。低加载速率下,混凝土试块主要是局部破坏和剪切破坏,当加载速率较快时,主要发生纵向劈裂;2)提高箍筋的屈服强度相当于增加混凝土损伤过程中的侧面围压,对约束混凝土试块的损伤起到一定的抑制作用;3)随着体积配箍率的增加,箍筋对混凝土试块损伤过程的约束作用越明显,有效抑制了试块的损伤演化过程。4)较高强度的混凝土试块在轴压过程中表现出更强的脆性,裂缝开展更快,适当增大混凝土强度有利于与箍筋相互配合抑制损伤演变。Abstract: The experiments were designed for the characterizing the damage progress in the stirrup confined concrete. Through the uniaxial compression test, the parametric study was conducted to investigate the effects of loading rate, concrete strength, stirrup diameter, volume stirrup ratio on the mechanical properties and damage behaviors of the confined concrete. The experimental results were analyzed and demonstrated that: 1) with the increase of loading rate, the elastic deformation stage of concrete is shortened; and the plasticity of the whole damage process is weakened; moreover, the damage shows more brittle patterns. At low loading rate, the local failure and shear failure were mainly observed. When the loading rate is reaching at a high level, the longitudinally splitting mainly occurs. 2) Increasing the yield strength of stirrups is equivalent to the enhancement of the lateral confining pressure during the damage process of concrete, which plays an essential role in restraining the damage of the sample; 3) With the increase of stirrup ratio, the confinement effect of stirrups on the damage process is becoming more obvious, which effectively constrains the damage evolution process. 4) The samples with higher strength concrete show more brittle behavior and faster crack development during axial compression. Appropriate increase of concrete strength is beneficial to cooperative work with stirrups to restrain the evolution of damage.
-
Key words:
- concrete /
- strength /
- stirrup confined /
- volume stirrup ratio /
- damage evolution
-
[1] 史庆轩,杨坤,姜维山,等. 高强箍筋约束高强混凝土柱的偏心受压试验研究[J]. 工业建筑,2009,39(10):76-80. [2] OZBAKKALOGLU T, AKIN E. Behavior of FRP-confined normal-and high-strength concrete under cyclic axial compression[J]. Journal of Composites for Construction, 2012, 16(4): 451-463. [3] NIE J G, HU H S, FAN J S, et al. Experimental study on seismic behavior of high-strength concrete filled double-steel-plate composite walls[J]. Journal of Constructional Steel Research, 2013, 88: 206-219. [4] 刘立军,贾明明,于晓辉. 箍筋约束混凝土的本构关系研究[J]. 工业建筑,2012,42(增刊1): 188-191. [5] KENT D C, PARK R. Flexural members with confined concrete[J]. Journal of the Structural Division, 1971, 97(7): 1969-1990. [6] MANDER J B, PRIESTLEY M J N, PARK R. Theoretical stress strain model for confined concrete columns[J]. Journal of Structural Engineering, 1988,114(8): 1804-1826. [7] 过镇海. 混凝土的强度和本构关系:原理与应用[M]. 北京:中国建筑工业出版社,2004: 58-63. [8] 刘磊,牛荻涛,李强,等. 锈蚀箍筋约束混凝土应力-应变本构关系模型[J]. 建筑材料学报,2018,21(5): 811-816. [9] JANG I Y, PARK H G, KIM Y G, et al. Flexural behavior of high-strength concrete beams confined with stirrups in pure bending zone[J]. International Journal of Concrete Structures and Materials, 2009, 3(1): 39-45. [10] 赵作周,张石昂,贺小岗,等. 箍筋约束高强混凝土受压应力-应变本构关系[J]. 建筑结构学报,2014,35(5):96-103. [11] 丁红岩,刘源,邱实. 高强箍筋约束高强混凝土轴心受压试验研究[J]. 建筑结构,2015,45(12):7-12. [12] 任晓丹,刘凯,魏公涛,等. 不同加载速率下箍筋约束混凝土力学性能试验研究[J]. 建筑结构学报,2017,38(3):141-150. [13] LI Z, PENG Z, TENG J, et al. Experimental study of damage evolution in circular stirrup-confined concrete[J]. Materials, 2016, 9(4), 278. [14] 曹胜涛,李志山. 约束混凝土单轴弹塑性损伤本构模型[J]. 工程力学,2017,34(11): 116-125. [15] 中华人民共和国住房和城乡建设部. 混凝土结构设计规范:GB 50010—2010[S]. 北京:中国建筑工业出版社,2011. [16] 中华人民共和国住房和城乡建设部. 混凝土物理力学性能试验方法标准:GB/T 50081—2019[S]. 北京:中国建筑工业出版社,2019. [17] SHEIKH S A, UZUMERI S M. Analytical model for concrete confinement in tied columns[J]. Journal of the Structural Division, 1982, 108(12): 2703-2722. [18] 杨光松. 损伤力学与复合材料损伤[M]. 北京:国防工业出版社,1995. [19] 滕军,李祚华,李安,等. 箍筋约束混凝土单轴受压塑性损伤本构模型[J]. 工程力学,2014,31(增刊1):189-194.
点击查看大图
计量
- 文章访问数: 18
- HTML全文浏览量: 2
- PDF下载量: 0
- 被引次数: 0