摘要
为了研究预加力对预应力混凝土梁桥开裂梁体刚度效应的影响,以公路桥梁中常用的预应力混凝土小箱梁和T梁为研究对象,基于设计规范中开裂预应力混凝土受弯构件刚度计算原理,采用统计分析、室内试验梁和实桥试验相结合方法,分析开裂预应力混凝土梁受拉区预压应力与梁体短期抗弯刚度的关系。结果表明:小箱梁和T梁受拉区混凝土开裂后,随预加力在受拉区混凝土所产生预压应力的增大,开裂梁体短期抗弯刚度提高;对于开裂预应力混凝土梁桥,采用增设体外预应力钢束的加固方法进行加固,可以有效地提高梁体短期抗弯刚度,较好地抑制梁体受力裂缝的发展。
To study the influence of pre-applied force on the rigidity effect of the cracked beams of prestressed concrete beam bridge,the commonly-used small prestressed concrete box beam and T beam in highway bridges were taken as the study objects,The relations between the pre-applied compressive stress in the tensile area of the cracked prestressed concrete beam and the short-term anti-bending rigidity of the beams was analyzed,based on the rigidity calculation theory for the cracked bending prestressed concrete components in the design code and by the combined use of the statistical analysis,indoor testing beams and actual bridge testing.The results of the analysis indicate that when the concrete in the tensile area of the small box beam bridge and T beam bridge cracked,the short-term anti-bending rigidity of the cracked beam was improved,as the pre-applied compressive stress induced by the pre-applied force in the tensile area concrete increased.For the cracked prestressed concrete beam bridge,the strengthening method of adding external prestressing tendons can effectively improve the short-term anti-bending rigidity of the beams and better suppress the propagation of the cracks in the beams.
出处
《世界桥梁》
北大核心
2016年第1期50-54,共5页
World Bridges
基金
山西省交通运输厅科技项目(2013-1-6)
关键词
预应力混凝土梁
开裂
预加力
刚度效应
开裂弯矩
短期抗弯刚度
理论分析
试验
prestressed concrete beam
cracking
pre-applied force
rigidity effect
cracking bending moment
short-term anti-bending rigidity
theoretical analysis
testing
