[1]汪昕,张继文.嵌入式FRP抗剪增强梁斜裂缝水平投影长度计算[J].东南大学学报(自然科学版),2008,38(5):779-783.[doi:10.3969/j.issn.1001-0505.2008.05.008]
 Wang Xin,Zhang Jiwen.Calculation of horizontal projection length of diagonal cracks in near-surface mounted FRP shear strengthened beams[J].Journal of Southeast University (Natural Science Edition),2008,38(5):779-783.[doi:10.3969/j.issn.1001-0505.2008.05.008]
点击复制

嵌入式FRP抗剪增强梁斜裂缝水平投影长度计算()
分享到:

《东南大学学报(自然科学版)》[ISSN:1001-0505/CN:32-1178/N]

卷:
38
期数:
2008年第5期
页码:
779-783
栏目:
土木工程
出版日期:
2008-09-20

文章信息/Info

Title:
Calculation of horizontal projection length of diagonal cracks in near-surface mounted FRP shear strengthened beams
作者:
汪昕 张继文
东南大学土木工程学院, 南京 210096
Author(s):
Wang Xin Zhang Jiwen
School of Civil Engineering, Southeast University, Nanjing 210096, China
关键词:
嵌入式FRP 斜裂缝水平投影长度 变角空间桁架模型 剪跨比 纵筋-箍筋强度比 最小二乘法
Keywords:
near-surface mounted FRP horizontal projection length of diagonal cracks variable-angle space truss model shear span ratio strength ratio of longitudinal steels and stirrups method of least square
分类号:
TU375.1
DOI:
10.3969/j.issn.1001-0505.2008.05.008
摘要:
为计算嵌入式FRP抗剪增强梁在四点加载作用下的斜裂缝水平投影长度,利用投影长度经验公式和变角空间桁架模型分别研究了剪跨比和纵筋-箍筋强度比对投影长度的影响,在此基础上综合考虑两者的相互关系,同时根据9根FRP嵌入式增强梁的实测试验数据,采用最小二乘法拟合斜裂缝投影长度计算公式.分析结果表明,单独考虑剪跨比和纵筋-箍筋强度比都不能很好地预测斜裂缝水平投影长度,而将两者结合能够较好地反应斜裂缝出现和发展的全过程,从而准确地计算斜裂缝水平投影长度.推导公式的计算结果和试验实测值取得了很好的吻合,误差小,离散程度低,同时还表明剪跨比是影响斜裂缝投影长度的主导因素.
Abstract:
To calculate horizontal projection length of diagonal cracks in near-surface mounted(NSM)FRP(fiber reinforced polymer)shear strengthened RC(reinforced concrete)beams under four-points loading, the empirical formulae and variable-angle space truss model were adopted respectively to investigate the influence factors that control the horizontal projection length. Based on this, two major influence factors, shear-span ratio and strength ratio of longitudinal steels to stirrups, were integrated and the formula was derived through fitting test datum of nine NSM FRP shear strengthened beams by means of least square method. Study results indicate that the horizontal projection length of diagonal cracks cannot be predicted accurately when considering shear span ratio and strength ratio of longitudinal steels to stirrups separately. However the horizontal projection length can be well predicted through integrating these two influence factors due to their well representation of the entire process of diagonal cracks’ occurring and development. As a result accurate computing results are verified through comparing with the test datum, while the formulae also indicates that shear span ratio is the major influence factor of horizontal projection length.

参考文献/References:

[1] 李荣,滕锦光,岳清瑞.FRP材料加固混凝土结构应用的新领域:嵌入式NSM加固法[J].工业建筑,2004,34(4):5-10.
  Li Rong,Teng Jinguang,Yue Qingrui,A new technique for strengthening concrete structures-near-surface mounted FRP reinforcement [J].Industrial Construction,2004,34(4):5-10(in Chinese)
[2] de Lorenzis L,Nanni A.Shear strengthening of reinforced concrete beams with near-surface mounted fiber-reinforced polymer rods[J].ACI Structural Journal,2001,98(1):60-68.
[3] Nanni A,Di Ludovico M,Parretti R.Shear strengthening of a PC bridge with NSM CFRP rectangular bars [J].Advances in Structural Engineering,2004,7(4):97-109.
[4] 汪昕.嵌入式碳纤维板条增强混凝土梁受弯与受剪承载力研究 [D].南京:东南大学土木工程学院,2006.
[5] 汪昕,张继文,吕志涛.槽形CFRP板条嵌入式增强混凝土梁受剪性能试验研究[J].土木工程学报,2008,43(8):53-59.
  Wang Xin,Zhang Jiwen,Lü Zhitao.Experimental study on shear strengthening of RC beams with embedded groove-shape CFRP laminates[J]. China Civil Engineering Journal,2008,43(8):53-59(in Chinese)
[6] 蓝宗建.混凝土结构设计原理[M],南京:东南大学出版社,2002.
[7] 粟一凡,材料力学(上册)[M].北京:高等教育出版社,1983(1995重印).
[8] 郝进锋,陈丽娟,赵文艳.钢筋混凝土设计中桁架模型的应用[J].四川建筑科学研究,2003,29(4):21-23.
[9] Khalifa A,Gold W J,Nanni A,et al.Contribution of externally bonded FRP to shear capacity of RC flexural members[J]. Journal of Composites for Construction,1998,2(4):195-202.
[10] 孙志忠,袁慰平,闻震初.数值分析 [M].2版.南京:东南大学出版社,2003.

备注/Memo

备注/Memo:
作者简介: 汪昕(1980—),男,博士生,wx8cai@126.com.
基金项目: 国家自然科学基金重点资助项目(50238030)、国家高技术研究发展计划(863计划)资助项目(2001AA336010)、江苏省自然科学基金重点资助项目(BK2000036-1)、新世纪优秀人才支持计划资助项目 、江苏省六大人才高峰资助项目.
引文格式: 汪昕,张继文.嵌入式FRP抗剪增强梁斜裂缝水平投影长度计算[J].东南大学学报:自然科学版,2008,38(5):779-783.
更新日期/Last Update: 2008-09-20