对大跨度钢箱连续梁桥施工过程最大悬臂状态进行非线性气动稳定性分析.提出基于风荷载非线性及结构几何非线性的气动稳定性分析理论.以某跨海大桥为工程背景,进行静风效应及风致抖振效应计算,明确钢箱梁最大悬臂状态位移响应均方根最大值,并以结构一期恒载作用下的位移为初始缺陷,静风力与抖振力作为荷载进行主梁最大悬臂状态非线性气动稳定性验算.结果表明,随着桥位处风速的增加,主梁悬臂端和跨中水平及竖向位移均呈现非线性增长趋势;结构的位移响应随着风攻角的正负变化而产生变化,风荷载的影响不容忽视.由于主梁刚度较大,在120 m·s-1风速范围内并没有出现失稳临界状态,但悬臂端水平及竖向位移变化幅度较大,为了保证人员安全及合龙顺利进行,提出3 种抗风措施.
Nonlinear aerodynamic stability of the maximum cantilever state of long- span continuous steel box bridge in the construction process was analyzed. Aerodynamic stability analyses based on wind load nonlinearity and geometry nonlinearity were proposed. A cross-sea bridge was taken as the subject, and the effects of static wind force and buffeting force were calculated and the maximum RMS of displacement response in the longest cantilever state was determined. The nonlinear aerodynamic stability analysis of the maximum cantilever state was carried out taking static wind force and buffeting force as the external load and the displacement under the dead load as initial defect. The results show that with the increase of wind speed, the horizontal and vertical displacement of the cantilever end and mid-span of the steel box girder both had a nonlinear increasing trend; the displacement response changed with the positive and negative transformation of wind attack angle, so the influence of wind load should not be ignored. Due to high stiffness of the steel box girder, the buckling critical state did not appear within the wind speed of 120 m·s-1, but the horizontal and vertical displacement of the cantilever end were relatively large. Three measures for wind resistance were proposed to ensure safety of the personnel and smooth closure process.
[1] Boonyapinyo V, Yamadah H, Miyata T. Wind-induced nonlinear lateraltorsional buckling of cable- stayed bridges[J]. Journal of Structural Engineering, ASCE, 1994, 120(2): 486-506.
[2] 程进, 肖汝诚, 项海帆. 大跨径斜拉桥非线性静风稳定性全过程分析[J]. 中国公路学报, 2000, 13(3): 25-29. Cheng Jin, Xiao Rucheng, Xiang Haifan. Full range nonlinear aerostatics analysis for long-span cable-stayed bridge[J]. China Journal of Highway and Transport, 2000, 13(3): 25-29.
[3] 方明山, 项海帆, 肖汝诚. 大跨径缆索承重桥梁非线性空气静力稳定 理论[J]. 土木工程学报, 2000, 33(2): 73-79. Fang Mingshan, Xiang Haifan, Xiao Rucheng. Nonlinear aerostatic stability theory of large-span cable-stayed bridge[J]. China Civil Engineering Journal, 2000, 33(2): 73-79.
[4] 陈峰, 胡大琳. 大跨径钢管混凝土拱桥非线性静风稳定性[J]. 长安大 学学报: 自然科学版, 2006, 26(2): 43-46. Chen Feng, Hu Dalin. Aerostatics stability of long-span concrete-filled steel tube arch bridge[J]. Journal of Chang'an University: Natural Science Edition, 2006, 26(2): 43-46.
[5] 张茜, 周旭红, 狄谨, 等. 大跨度钢箱梁斜拉桥施工过程风致抖振时域 分析及抗风措施[J]. 长安大学学报: 自然科学版, 2013, 33(1): 47-49. Zhang Qian, Zhou Xuhong, Di Jin, et al. Time- domain analysis of wind- induced buffet and wind- resistant measures for cable- stayed bridge with steel box girder at construction stage[J]. Journal of Chang'an University: Natural Science Edition, 2013, 33(1): 47-49.
[6] Fujino Y, Yoshida Y. Wind-induced vibration and control of Trans- Tokyo Bay crossing bridge[J]. Journal of Structural Engineering, ASCE, 2002, 128(8): 1012-1024.
[7] Ren D B, Qu Y, Yang L L. The analysis of wind vibration coefficient of long-span dome structures with different thickness[J/OL]. Proceedings, ASCE, 2012: 1196-1204. [2013-11-12]. http://dx.doi.org/10.1061/ 9780784412190.130.
[8] 陈政清. 工程结构的风致振动、稳定与控制[M]. 北京: 科学出版社, 2013. Chen Zhengqing. The wind-induced vibration, stability and control of engineering structure[M]. Beijing: Science Press, 2013.
[9] 陈政清. 桥梁风工程[M]. 北京: 人民交通出版社, 2005. Chen Zhengqing. The bridge wind engineering[M]. Beijing: China Communications Press, 2005.
[10] 中交公路规划设计院. JTG D60—2004 公路桥梁抗风设计规范[S]. 北京: 人民交通出版社, 2004. China Highway Planning and Design Institute. JTG D60—2004 Windresistent design specification for highway bridges[S]. Beijing: China Communications Press, 2004.
[11] Scanlan R H. The action of flexible bridges under wind buffeting theory[J]. Journal of Sound and Vibration, 1978, 60(2): 201-211.
[12] 曾攀. 有限元分析及应用[M]. 北京: 清华大学出版社, 2006. Zeng Pan. Finite element analysis and applications[M]. Beijing: Tsinghua University Press, 2006.
[13] 葛耀君. 大跨度悬索桥抗风[M]. 北京: 人民交通出版社, 2011. Ge Yaojun. Wind resistance of long span suspension bridges[M]. Beijing: China Communications Press, 2011.
[14] 项海帆. 现代桥梁抗风理论与实践[M]. 北京: 人民交通出版社, 2005. Xiang Haifan. Modern theory and practice on bridge wind resistance[M]. Beijing: China Communications Press, 2005.
[15] Li H N, Jing Q Y, Wang G X. Control of tuned liquid dampers for wind-induced skyscraper vibration[J]. Journal of Structural Engineering, ASCE, 2006, 188(155): 1-8.
