FRP筋钢纤维高强混凝土梁变形性能试验研究  

Experimental Study on Stiffness of FRP Bar and Steel Fiber Reinforced High-strength Concrete Beams

作　　者：朱海堂 程晟钊[2,3] 高丹盈 王仁龙[4] ZHU Haitang;CHENG Shengzhao;GAO Danying;WANG Renlong(College of Civil Engineering, Henan University of Engineering, Zhengzhou 451191,China;School of Water Conservancy Science & Engineering, Zhengzhou University, Zhengzhou 450001, China;China Construction Seventh Engineering Division Corp., Ltd., Zhengzhou 450004,China;Henan Water & Power Engineering Consulting Co., Ltd., Zhengzhou 450016,China)

机构地区：[1]河南工程学院土木工程学院,河南郑州451191 [2]郑州大学水利科学与工程学院,河南郑州450001 [3]中国建筑第七工程局有限公司,河南郑州450004 [4]河南省水利勘测设计研究有限公司,河南郑州450016

出　　处：《铁道学报》2020年第12期162-170,共9页Journal of the China Railway Society

基　　金：国家自然科学基金(51178433,51578510)。

摘　　要：将具有增强增韧作用的钢纤维掺入到FRP筋混凝土结构中,可解决FRP筋混凝土结构变形大、裂缝宽、脆性破坏等问题。对12根试件进行了四点受弯试验,研究了钢纤维掺加高度、钢纤维掺量、纵筋配筋率与FRP筋钢纤维高强混凝土梁跨中挠度间的关系。结果表明,钢纤维对裂缝出现后FRP筋混凝土量的刚度衰减有明显的抑制作用,当荷载为110 kN时,体积率为0.5%~2.0%的钢纤维使受弯梁的挠度最多减小了59.48%;钢纤维掺加高度达到梁截面高度的57%时,试件的变形与裂缝发展接近全截面掺加钢纤维的试件;随着FRP筋配筋率的提高,相同荷载下梁的跨中挠度逐渐减小,当FRP筋配筋率达到一定程度后,试验梁表现出了一定的延性。根据试验结果并收集了国内外共23根FRP筋钢纤维混凝土梁的研究数据,提出了基于有效惯性矩法的FRP筋钢纤维混凝土梁受弯刚度的建议计算方法,该建议方法能够较好预测梁的受弯刚度。In order to solve the large deflection,wide crack and brittle failure of the structures reinforced with FRP bars,a new structure,FRP bar and steel fiber reinforced high-strength concrete structure,was proposed.In this paper,12 specimens were cast and tested,to investigate the influences of the depth of steel fiber layer,steel fiber volume fraction and FRP reinforcement ratio on the mid-span deflection of FRP bar and steel fiber reinforced high-strength concrete beams.The result shows that the stiffness degradation of the FRP reinforced concrete can be effectively restrained by steel fibers after the crack occurs.At 110 kN load,the deflection of the beam can be reduced by 36.38%-59.48%with a steel fiber volume ratio of 0.5%to 2.0%.When the depth of steel fiber layer is at 0.57 times of the height of specimens,the deformation and crack development of the specimen are close to those of the specimen with the steel fibers distributed over the full section.With the increase of FRP reinforcement ratio,the mid-span deflection of the beam decreases under the same load and the test beam shows a certain degree of ductility.Based on the test results and the research data collected from 23 FRP steel fiber reinforced concrete beams at home and abroad a calculating method,which can be used for evaluating the stiffness of FRP bar and steel fiber reinforced high-strength concrete beams,was proposed.

关 键 词：FRP筋 钢纤维 变形 梁 刚度 

分 类 号：TU375[建筑科学—结构工程] TU528.57