(1 重庆大学土木工程学院, 重庆 400045; 2 重庆大学山地城镇建设与新技术教育部重点实验室， 重庆 400045;  3 中国建筑科学研究院有限公司， 北京 100013）

［摘要］通过采用HRB500钢筋和LC50高强轻骨料混凝土的剪跨比为3的不同受拉纵筋率的无腹筋梁试验，研究了试验梁开裂和极限承载力阶段的受力特征，并着重研究了低受拉纵筋率对梁破坏模式的影响规律。结合已有的试验研究结果，对我国现行《轻骨料混凝土结构规程》（JGJ 12—2006）中梁的最小受拉纵筋配筋率取值进行了检验。研究结果表明轻骨料混凝土梁抗剪承载力计算时应当考虑受拉纵筋率的影响。

［关键词］高强轻骨料混凝土； 高强钢筋； 最小配筋率； 破坏模式

中图分类号：TU375-1文献标识码：A文章编号：1002-848X(2019)10-0064-06

Experiments on behavior of high-strength lightweight concrete beams without web reinforcement with low longitudinal reinforcement ratio

Tan Haoyue1, 2,  Zhang Chuan1, 2, Zhu Aiping3, Ji Ke1, 2, Wang Xinlei1, 2

(1 School of Civil Engineering, Chongqing University, Chongqing 400045, China; 2 Key Laboratory of New Technology for Construction of Cities in Mountain Area (Chongqing University), Ministry of Education, Chongqing 400045, China; 3 China Academy of Building Research, Beijing 100013, China)

Abstract:Experiments on light weight concrete beams without web reinforcement with different longitudinal reinforcement ratios were carried out, using HRB500 steel bar and high-strength lightweight concrete LC50. The shear span ratio of these beams is 3. Characteristics of cracking and ultimate strength were investigated. In particular, the influence of low longitudinal reinforcement ratio on failure mode of beams was studied in depth. Based on the obtained experimental results, the codified value of minimum longitudinal reinforcement ratio of lightweight concrete beams in Technical specification for lightweight aggregate concrete structures (JGJ 12—2006) was examined. The findings  show that the effect of longitudinal reinforcement ratio on shear capacity should be considered in shear design equations for lightweight concrete beams.

Keywords:high-strength lightweight concrete; high-strength reinforcement; minimum longitudinal reinforcement ratio; failure mode

通讯作者：张川，博士，教授，Email: zchuan08@126.com。