Experimental Research on Bearing Behavior of New-to-Old Concrete Interface in Arch Bridge Strengthening
-
摘要: 结合工程实例,制作了2个拱圈试件,通过一次性加载破坏试验,对试件的破坏特征、新老混凝土结合面的工作性能及应力、应变分布进行了研究.试验结果表明:受荷初期,结合面的抗剪主要由无植筋时新老混凝土的粘结承担;当剪应力达到新老混凝土粘结抗剪强度后,主要由植筋承担.在裂缝附近区域、靠近裂缝和远离裂缝的非裂缝区域,结合面的粘结剪应力分布不同,主要区别在纵向钢筋开始屈服到试件破坏阶段.在此阶段,裂缝附近区域结合面的粘结剪应力随荷载增大线性减小,在靠近裂缝的非裂缝区域基本不变,而在远离裂缝的非裂缝区域线性增大,直至试件破坏.粘结剪应力最大值出现在拱顶裂缝附近.Abstract: Two models of arch ring were made to research the bearing behaviors of new-to-old concrete interface in arch bridge strengthening.Destructive experiments were carried out on the two models to investigate their failure characteristics and service behaviors and the distributions of stress and strain on new-to-old concrete interface.The experimental result shows that the shear-bearing capacity of the interface is given by the bond of new and old concrete without embedded steel bars at the early stage of loading.When shear stress increases to the bond shear strength of new and old concrete,the shear-bearing capacity of the interface is mainly given by embedded steel bars.The distribution of bond shear stress on the interface is different in different regions at the stage from yielding of longitudinal reinforcement to the failure of specimens.At the stage,the bond shear stress decreases linearly in the region near cradks,does not change in the region away from cracks and increases linearly in the region away far from cracks.
-
堪润水,胡钊芳,师长斌.公路旧桥加固技术与实例[M].北京:人民交通出版社,2002:124-126.[2] 敖进淘,谢惠才,熊光晶,等.影响新老混凝土界面粘结强度的主要因素[J].工程力学,1997,2(增刊):328-333.[3] 闫国新,张雷顺.新老混凝土粘结面粗糙度处理方法综述[J].混凝土,2007(8):98-100.YAN Guoxin,ZHANG Leishun.Method review of the interfacial roughness of new to old concrete[J].Concrete,2007(8):98-100.[4] AUSTIN S,ROBINS P,PAN Y G.Tensile bond testing of concrete repairs[J].Materials and Struetures,1995,28(3):249-259.[5] HINDO K R.In-place bond testing and surface preparation of concrete[J].Concrete International,1990(4):46-48.[6] 赵志方,赵国藩,刘健,等.新老混凝土粘结抗拉性能的试验研究[J].建筑结构学报,2001,22(2):52-56.ZHAO Zhifang,ZHAO Guofan,LIU Jian,et al.Experimental study on adhesive tensile performance of young on old concrete[J].Journal of Building Structure,2001,22(2):52-56.[7] 高剑平,潘景龙,王雨光.不同界面剂对新旧混凝土粘结强度影响的试验研究[J].哈尔滨建筑大学学报,2001,34(5):25-29.GAO Jianping,PAN Jinglong,WANG Yuguang.Effect of different bonding agents on bond strength between fresh concrete and hardened concrete[J].Journal of Harbin University of Civil Engineering and Architecture,2001,34(5):25-29.[8] 管大庆,陈章洪,石韫珠.界面处理对新老混凝土粘结性能的影响[J].混凝土,1994(5):16-22.[9] 王振领,林拥军,钱永久.新老混凝土结合面抗剪性能试验研究[J].西南交通大学学报,2005,40(5):600-604.WANG Zhenling,LIN Yongjun,QIAN Yongjiu.Experimental research on shear properties of new-to-old concrete interface[J].Journal of Southwest Jiaotong University,2005,40(5):600-604.[10] 王振领.新老混凝土粘结理论与试验及在桥梁加固工程中的应用[D].成都:西南交通大学土木工程学院,2006.
点击查看大图
计量
- 文章访问数: 1598
- HTML全文浏览量: 62
- PDF下载量: 46
- 被引次数: 0