深度锈蚀的无腹筋钢筋混凝土梁承载机理分析*
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（1 昆明理工大学, 昆明 650500；2 国立长冈工业高等专门学校, 新潟 940-8532；3 中央大学, 东京 112-8551；4 东电设计株式会社，东京 112-0015；5 东京电力株式会社, 横滨 230-8510）［摘要］以位移控制加载，进行了深度锈蚀的无腹筋钢筋混凝土梁的四点受弯加载试验。通过锈蚀梁的纵筋的应变分布，计算各加载水平下纵筋与混凝土之间的粘结应力。试验表明，深度锈蚀梁和非锈蚀梁的应变分布和应力历程有着明显的差异；加载初期阶段，剪跨区域的平均粘结应力逐步增加至峰值，锚固区域的平均粘结应力无明显增加；加载后期阶段，剪跨区域的平均粘结应力逐步降低，而锚固区域的平均粘结应力显著增加；随着荷载的增加，深度锈蚀梁的承载机理由“梁效应”向“拱效应”转变。基于“拱效应”的受力特征，提出了深度锈蚀梁极限荷载的计算方法。［关键词］深度锈蚀钢筋混凝土梁; 承载机理; 极限承载力; 粘结应力; 梁效应; 拱效应中图分类号：TU375.1 文献标识码：A 文章编号：1002-848X(2014)05-0034-06Study on load resisting mechanism of seriously corroded reinforced concrete beam without stirrups in shear spanDong Wei1, Murakami Yuki2, Oshita Hideki3, Suzuki Shuichi4, Tsutsumi Tomoaki5(1 Kunming University of Science and Technology, Kunming 650500, China; 2 Nagaoka National College of Technology, Niigata 940-8532, Japan; 3 Chuo University, Tokyo 112-8551, Japan; 4 Tokyo Electric Power Services Co., Ltd., Tokyo 112-0015, Japan; 5 Tokyo Electric Power Co., Ltd., Yokohama 230-8510, Japan)Abstract: Four-point static bending tests of the seriously corroded reinforced concrete beam were conducted under displacement control. The bond stress between the main rebar and the concrete at any load level was computed, based on the longitudinal strain of the main rebar. It can be concluded that the strain distribution and the bond stress history of the seriously corroded reinforced concrete beam are different from that of non-corroded beam. The bond stress in the shear span increases to peak value and the bond stress in the anchorage region dose not increase significantly at the early loading stage. But the bond stress in the shear span decreases and the bond stress in the anchorage region is extremely higher at the later loading stage. With the increase of the applied load, arch action, instead of beam action, has achieved a dominant position in the seriously corroded reinforced concrete beam. The calculating method of the ultimate strength for the seriously corroded reinforced concrete beam was proposed based on the arch action.Keywords: seriously corroded reinforced concrete beam; load resisting mechanism; ultimate strength; bond stress; beam action; arch action*云南省级昆明理工大学人才培养项目（KKSY201204157）。作者简介：董卫，博士，讲师，Email：touicn@163.com。参考文献［1］牛荻涛, 翟彬, 王林科, 等. 锈蚀钢筋混凝土梁的承载力分析［J］. 建筑结构, 1999, 29(8): 23-25.［2］袁迎曙, 贾福萍, 蔡跃. 锈蚀钢筋混凝土梁的承载力分析［J］. 土木工程学报, 2001 (3): 49-54，98.［3］颜桂云, 孙炳楠, 王泽军, 等. 锈蚀钢筋混凝土压弯构件抗震性能的试验研究［J］. 建筑结构, 2003, 33(2): 16-18，50.［4］牛荻涛, 陈新孝, 王学民. 锈蚀钢筋混凝土压弯构件抗震性能试验研究［J］. 建筑结构, 2004, 34(10): 36-45.［5］KAYSER J, NOWAK A. Capacity loss due to corrosion in steel-girder bridges［J］. ASCE, 1989, 115(6): 1525-1537.［6］孙彬, 牛荻涛, 王庆霖. 锈蚀钢筋混凝土梁抗弯刚度分析与计算［J］. 建筑结构, 2004, 34(10): 42-45.［7］徐善华, 曾柯, 拧慷涛. 锈蚀钢筋混凝土受弯构件正截面承载力计算模型［J］. 建筑结构, 2006, 36(10): 79-81，97.［8］VAL D，CHERNIN L. Serviceability reliability of reinforced concrete beams with corroded reinforcement［J］. Journal of Structural Engineering, 2009, 135(8) : 896-905.［9］大即信明, 鈴木慎也. 耐久性に優れたコンクリート構造物—港湾構造物［J］. 土木学会論文集, 1986, 372: 29-39.［10］苗吉军, 李乌江, 刘延春, 等. 沿海某混凝土框架结构钢筋锈蚀原因分析与修复加固对策［J］. 建筑结构, 2010, 40(2): 81-83，80.［11］SCOTT R H. Intrinsic mechanisms in reinforced concrete beam-column connection behaviour［J］. ACI Structural Journal, 1996, 93(3): 336-346.［12］村上祐貴, 木下哲秀, 鈴木修一, など. 鉄筋腐食を生じたRC梁部材の残存曲げ耐力性状に関する研究［J］. コンクリート工学論文集, 2006, 17(1):61-74.
