无腹筋RUHTCC梁抗剪性能试验研究  

Experimental investigation on shear responses of RUHTCC beams without stirrups

作　　者：侯利军[1] 陈达[1] 徐世烺[2] 张秀芳[3] 

机构地区：[1]河海大学海岸灾害与防护教育部重点实验室,南京210098 [2]浙江大学建筑工程学院,杭州310058 [3]大连理工大学建设工程学部,大连116024

出　　处：《东南大学学报（自然科学版）》2014年第1期133-139,共7页Journal of Southeast University：Natural Science Edition

基　　金：水利部公益性行业科研专项资助项目(201301052);中央高校基本科研业务费资助项目(2013B03614);浙江省重点科技创新团队资助项目(2010R50034)

摘　　要：为了探究超高韧性水泥基复合材料(UHTCC)的抗剪性能,以配筋率和剪跨比为参数,对跨中荷载作用下的6根钢筋增强UHTCC(RUHTCC)梁和4根钢筋混凝土(RC)对比梁进行了受弯试验.对比研究了RUHTCC梁的抗剪性能,包括裂缝扩展形态、荷载-挠度曲线、剪切开裂荷载、极限剪切能力以及剪切强度等.试验结果表明,随着配筋率的增大和剪跨比的减小,RUHTCC梁的破坏模式由弯剪破坏转变为剪压破坏,极限剪切承载能力逐渐增大.RUHTCC梁的极限剪切能力约为RC梁的2倍,平均抗剪强度约为UHTCC抗拉强度的0.86倍;RUHTCC梁表现出稳态的多条细密斜裂缝扩展模式,在正常使用极限状态下,其最大裂缝宽度低于0.1 mm.基于RUHTCC梁良好的裂缝控制能力以及较高的富余剪切承载能力,不需设置最小配箍率.In order to understand the shear behavior of ultrahigh toughness cementifious composite （ UHTCC）, the bending tests on six reinforced UHTCC （RUHTCC） beams and four reinforced con- crete （RC） comparison beams were performed under a concentrated loading at mid-span. The varied parameters were the shear-span ratio and the reinforcement ratio. The shear responses of the RU- HTCC beams and those of the RC beams were compared, including the diagonal crack pattern, the load-deflection curve, the shear cracking load, the ultimate shear capacity and the shear strength, etc. The experimental results indicate that with the increase in the reinforcement ratio and the de- crease in the shear-span ratio, the failure mode of the RUHTCC beams transforms from flexure-shear to shear-compression and the ultimate shear capacity rises gradually. The ultimate shear capacity of the RUHTCC beams is about twice that of the RC beams, and the average ultimate shear strength of the RUHTCC beams is about 0. 86 times that of the ultimate tensile strength of the UHTCC. The RUHTCC beams present the stable propagation of multiple fine diagonal cracks, with the maximum crack width below 0. 1 nun under the ultimate service condition. The minimum web reinforcement ratio is not required for the RUHTCC beams due to its large post-cracking reserve shear capacity and fine crack controlling capability.

关 键 词：抗剪性能试验 RC梁 正常使用极限状态 无腹筋 水泥基复合材料 钢筋混凝土 剪切强度 剪切能力 

分 类 号：TU317[建筑科学—结构工程]