（1 华北理工大学建筑工程学院， 唐山  063009； 2 河北省地震工程研究中心， 唐山 063009；3 贝卡尔特应用材料科技(上海)有限公司， 上海 200131）

［摘要］纤维混凝土梁受弯或受剪时纤维的选取对纤维发挥抗弯或抗剪作用尤其重要。进行了15组混杂纤维自密实混凝土梁的弯曲韧性试验和13根纤维增强钢筋自密实混凝土梁的抗剪性能试验研究，将梁的抗弯、抗剪性能与相同条件的以往研究结果进行对比。结果表明，单掺钢纤维时，长度50mm、长径比80的钢纤维混凝土梁弯曲韧性好于长度35mm、长径比64的钢纤维混凝土梁，对梁的抗剪贡献大；混杂长度50mm、长径比80的钢纤维混凝土梁与长度45mm、长径比60的合成纤维混凝土梁的剩余抗弯强度fR,4 高于混杂长度50mm、长径比80的钢纤维混凝土梁与长度30mm、长径比45的合成纤维混凝土梁，对梁的抗剪贡献大；钢纤维和合成纤维类型一定时，在混凝土梁中掺加掺量为（40+4）kg/m3的混杂纤维在提高梁的抗弯性能和抗剪性能方面好于掺加掺量为（30+5）kg/m3的混杂纤维，掺加掺量为（30+5）kg/m3的混杂纤维好于掺加掺量为（20+6）kg/m3的混杂纤维。

［关键词］混杂纤维； 钢筋混凝土梁； 弯曲韧性； 抗剪性能； 纤维选取

中图分类号：TU375文献标识码：A文章编号：1002-848X(2017)13-0078-07

Comparison of fibers in self-consolidating concrete flexural and shear beams

You Zhiguo1,2, Fu Xiuyan1,2, Zhou Yunlong1,2, Wang Peng1,2, Chen Xiangyu3, Dong Xuechao1,2

(1 College of Civil and Architectural Engineering, North China University of Science and Technology, Tangshan 063009, China; 2 Earthquake Engineering Research Center of Hebei Province, Tangshan 063009, China; 3 Bekaert Applied Material Technology (Shanghai) Co.,Ltd., Shanghai, 200131, China)

Abstract:The fiber choices in fiber reinforced  concrete flexural and shear beam are very important to bending and shear actions played by fibers. The flexural toughness experiments on 15 series of hybrid fibers reinforced self-consolidating concrete beams and shear behavior experiments on 13 fiber reinforced self-consolidating concrete beams were studied. The bending and shear resistance  were compared to those of the past studies with similar experimental conditions. The research results can be obtained as follows.  When only steel fiber is added to beam, the flexural toughness and the contribution to shear resistance of steel fiber reinforced concrete with steel fiber of length of 50mm and length-to-diameter ratio of 80 are better than those of steel fiber reinforced concrete with steel fiber of length of 35mm and length-to-diameter ratio of 64. The residual bending strength fR,4 and the contribution to shear load of hybrid fiber reinforced concrete with steel fiber of length of 50mm, length-to-diameter ratio of 80 and synthetic fiber of length of 45mm, length-to-diameter ratio of 60 are better than those of hybrid fiber reinforced concrete with steel fiber of length of 50mm, length-to-diameter of 80 and synthetic fiber of length of 30mm and length-to-diameter of 45. For steel fiber and synthetic fiber with the same fiber type, the flexural and shear behavior of beam with hybrid fiber（40+4）kg/m3 is better than that of beam with hybrid fiber（30+5）kg/m3. The flexural and shear behavior of beam with hybrid fiber（30+5）kg/m3 is better than that of beam with hybrid fiber（20+6）kg/m3. 

Keywords:hybrid fiber; reinforced concrete beam; flexural toughness; shear behavior; fiber choice

*国家自然科学基金（51478161，51608196），华北理工大学培育基金项目(GP201523)。

作者简介：尤志国，博士，副教授，硕士研究生导师，Email:youzhiguo119@163.com。