超高强钢筋ECC梁受弯性能试验研究及参数分析  

Experimental Study and Parametric Analysis of Flexural Behaviors of Ultra High Strength Rebar Reinforced ECC Beams

作　　者：廖桥 李碧雄[1,2] 章一萍 LIAO Qiao;LI Bixiong;ZHANG Yiping(College of Architecture and Environment,Sichuan University,Chengdu 610065,China;Key Laboratory of Deep Underground Science and Engineering Ministry of Education,Sichuan University,Chengdu 610065,China;College of Civil Engineering,Tongji University,Shanghai 200092,China;Sichuan Provincial Architectural Design and Research Institute,Chengdu 610000,China)

机构地区：[1]四川大学建筑与环境学院,四川成都610065 [2]四川大学深地科学与工程教育部重点实验室,四川成都610065 [3]同济大学土木工程学院,上海200092 [4]四川省建筑设计研究院,四川成都610000

出　　处：《应用基础与工程科学学报》2022年第1期121-133,共13页Journal of Basic Science and Engineering

基　　金：国家重点研发计划项目(2018YFC1508802_01-02);国家自然科学基金项目(51678379);四川省科技计划应用基础研究项目(19YYJC2601)。

摘　　要：为减少钢筋用量并增强梁的控裂能力和延性性能,将具有应变硬化和多缝开裂能力的工程用水泥基复合材料(Engineered Cementitious Composites,ECC)与超高强钢筋组合成超高强钢筋ECC梁(Ultra High Strength Rebar Reinforced ECC Beam,UHSRRE梁).为深入研究该类梁的受弯性能,对5根UHSRRE梁(纵筋为HRB500级钢筋)和1根普通钢筋ECC梁进行四点弯曲试验,通过比较弯曲试验结果与理论分析结果以验证UHSRRE梁受弯计算理论的合理性,基于受弯计算理论分析纵筋配筋率、ECC单轴受拉极限应变和单轴受压峰值强度对UHSRRE梁(纵筋为HRB600级钢筋)的特征弯矩(开裂弯矩、屈服弯矩和极限弯矩)和受压区高度的影响.研究表明:UHSRRE梁的耐久性能和能量耗散能力有望得到提高;基于UHSRRE梁受弯计算理论得到的结果与受弯试验结果吻合良好;随配筋率增加,UHSRRE梁的屈服弯矩、极限弯矩和对应的受压区高度明显增大;ECC的单轴受拉极限应变越大,UHSRRE梁受弯产生的裂缝数量越多,但特征弯矩和受压区高度变化很小;随ECC单轴受压峰值强度的增大,受压区高度显著减小,屈服弯矩和极限弯矩提高不明显.For decreasing the amount of steel bars used in civil engineering and strengthening the crack width control ability and ductility of beams,it is an effective way that engineered cementitious composites(ECC)with strain hardening and multiple micro-cracking is combined with ultra high strength rebar to form a ultra high strength rebar reinforced ECC(UHSRRE)beam.In order to further study the flexural behaviors of UHSRRE beams,five UHSRRE beams with HRB500 rebar and one ordinary strength rebar reinforced ECC beam were tested by fourpoint bending tests,and calculation theory about UHSRRE beams was verified by comparing experimental and theoretical results.And then the influences of parameters(i.e.longitudinal reinforcement ratio,uniaxial ultimate tensile strain and compressive strength of ECC)on the characteristic moment(i.e.cracking,yielding and ultimate moment)and height of compression zone of UHSRRE beams with HRB600 rebar were analyzed based on this theory.The results show that the durability and energy dissipation capability of UHSRRE beams will be improved due to the existence of many micro-cracks.The theoretical results are in good agreement with the experimental results.With the increase of the reinforcement ratio,yielding and ultimate moments as well as the corresponding depth of compression zone increase significantly.When the uniaxial ultimate tensile strain of ECC is improved,number of cracks in UHSRRE beams increases,but the variation of the characteristic moment and height of compression zone is relatively slight.As the uniaxial compressive strength of ECC raises,the depth of compression zone decreases obviously,but yielding and ultimate moments enlarge slightly.

关 键 词：工程用水泥基复合材料 超高强钢筋 受弯性能 纵筋配筋率 单轴受拉极限应变 单轴受压峰值强度 

分 类 号：TU375.1[建筑科学—结构工程]