基于环境振动测试的框架结构主裙楼动力特性分析

PDF(2408 KB)

振动与冲击 ›› 2016, Vol. 35 ›› Issue (10) : 174-179.

论文

刘佩1,2，连鹏宇1

作者信息 +

Dynamic characteristics analysis of a frame structure with the main building and podium based on ambient vibration test data

LIU Pei1,2, LIAN Peng-yu1

Author information +

文章历史 +

摘要

对某未设防震缝的钢筋混凝土框架结构主楼和裙房进行环境振动测试，并对其动力特性进行分析。测点分别布置在主楼左右两个楼梯间、顶层楼板和裙房井字梁大跨楼板上。利用实测加速度数据并通过改进的频域分解法，识别得到了结构的五阶模态参数。识别结果表明：各测试方案得到的识别结果一致，自振频率的变异性较阻尼比的变异性小；前四阶模态由主楼的振动引起，第五阶模态为裙房楼板的一阶竖向振动模态；由于结构的不对称性，识别得到的前三阶振型均带有扭转效应；模态参数识别过程中的可疑模态可能来源于主楼和裙房的动力相互作用。建立了所测结构的有限元模型，得到了五阶自振频率和振型，与识别结果吻合较好；分析了主楼和裙房之间的不同连接方式对整体结构自振频率和振型的影响，结果表明主楼和裙房的固结连接与铰接连接对自振频率基本没有影响，而设置防震缝与否对自振频率影响较大，且振型出现顺序均不会发生变化。

Abstract

Ambient vibration tests of a frame structure formed by the main building and podium without seismic joint were conducted and dynamic characteristics of the structure were analyzed. The sensors employed for the tests were instrumented on the right and left stairwells, the fourth floor of the main building and the large span floor of the podium with grillage beams. With the tested acceleration data and improved frequency domain decomposition method, modal parameters of five modes were identified. Identification results from different tests are approximate. Variations of identified natural frequencies are smaller than those of damping ratios. The first four modes are induced by the vibrations of the main building. The fifth mode is the first vertical bending mode of the podium. Torsional behavior appears in the first three modes due to asymmetry of the structure. The spurious modes during identification may be due to dynamic interactions of the main building and podium. Finite element model of the tested structure was constructed and five modes were obtained, which agree well with the identification results. Influence of different connection forms between the main building and podium on the natural frequencies and mode shapes of the structure were analyzed. Results show that fixed or pinned connections between the main building and podium have almost no influence, while presence of seismic joint has large influence on the natural frequencies of the structure. The order of the mode shapes does not change for all the cases.

导出引用

刘佩1,2，连鹏宇1. 基于环境振动测试的框架结构主裙楼动力特性分析[J]. 振动与冲击, 2016, 35(10): 174-179

LIU Pei1,2, LIAN Peng-yu1. Dynamic characteristics analysis of a frame structure with the main building and podium based on ambient vibration test data[J]. Journal of Vibration and Shock, 2016, 35(10): 174-179

参考文献

[1] 张保良, 张鹏飞. 带裙房高层建筑的沉降缝设置探讨[J]. 建筑结构, 1996, 26(6): 21-26.
ZHANG Bao-liang, ZHANG Peng-fei. Discussion on presence of settlement joint for high-rise buildings with podium [J]. Building Structure, 1996, 26(6): 21-26.
[2] 刘德稳, 郭春丽, 陈虎, 雷敏. 主裙楼不同连接方式对L型带裙房高层建筑结构-基础-地基共同作用影响研究[J]. 科学技术与工程, 2013, 13(21): 6156-6163.
LIU De-wen, GUO Chun-li, CHEN Hu, LEI Min. Concurrent functional influence research of L-shaped podiums high-rise structure connected in different ways [J]. Science Technology and Engineering, 2013, 13(21): 6156-6163.
[3] 郗俊玲. 高层建筑结构主体与裙楼非独立布置方案研究[D]. 西安：西安理工大学, 2008.
XI Jun-ling. Study on layout schedule of the main body of high-rise building structure and the non-independent body of annex building [D]. Xi’an: Xi’an university of Technology, 2008.
[4] 刘晶波, 汪勇. 主-裙楼结构体系的动力特性及地震反应分析[J]. 建筑结构学报, 2000, 21(2): 36-43.
LIU Jing-bo, WANG Yong. Dynamic properties and seismic response of high-rise building with podium [J]. Journal of Building Structures, 2000, 21(2): 36-43.
[5] Soyoz S, Taciroglu E, Orakcal K, Nigbor R, Skolnik D, Lus H, Safak E. Ambient and forced vibration testing of a reinforced concrete building before and after its seismic retrofitting [J]. ASCE, Journal of Structural Engineering, 2013, 139(10): 1741-1752.
[6] Şahin A, Bayraktar A, Özcan D M, Sevim B, Altunışık A C, Türker T. Dynamic field test, system identification, and modal validation of an RC Minaret: Preprocessing and postprocessing the wind-induced ambient vibration data [J]. ASCE Journal of Performance of Constructed Facilities, 2011, 25(4): 336-356.
[7] Au S K, Zhang F L. Ambient modal identification of a primary-secondary structure by fast Bayesian FFT method [J]. Mechanical Systems and Signal Processing, 2012, 28(4): 1318-1325.
[8] Au S K, Ni Y C, Zhang F L, Lam H F. Full scale dynamic testing and modal identification of a coupled floor slab system [J]. Engineering Structures, 2012, 37(4): 167-178.
[9] Chen W H, Lu Z R, Lin W et al. Theoretical and experimental modal analysis of the Guangzhou New TV Tower [J]. Engineering Structures, 2011, 33(12): 3628-3646.
[10] Foti D, Diaferio M, Giannoccaro N I, Mongelli M. Ambient vibration testing, dynamic identification and model updating of a historic tower [J]. NDT & E International, 2012, 47(4): 88-95.
[11] 孙雷, 刘福胜, 王少杰, 崔兆彦. 短周期村镇砌体建筑振动特性实测与抗震性能分析[J]. 土木工程学报, 2013, 46(s2): 57-62.
SUN Lei, LIU Fu-sheng, WANG Shao-jie, CUI Zhao-yan. Dynamic characteristic test and seismic performance analysis of short-period masonry [J]. China Civil Engineering Journal, 2013, 46(s2): 57-62.
[12] 非明伦, 周光全, 卢永坤等. 昆明高（超高）层建筑环境振动特性实测与统计分析[J]. 地震研究, 2012, 35(1): 117-127.
FEI Ming-lun, ZHOU Guang-quan, LU Yong-kun et al. Actual measurement and statistical analysis of ambient vibration characteristics of the high-rise (skyscraper) buildings in Kunming [J]. Journal of Seismological Research, 2012, 35(1): 117-127.
[13] 施卫星, 王进. 钢筋混凝土框架结构动力特性研究[J]. 地震工程与工程振动, 2010, 30(6): 87-91.
SHI Wei-xing, WANG Jin. Research on dynamic characteristics of reinforced concrete frame structures [J]. Journal of Earthquake Engineering and Engineering Vibration, 2010, 30(6): 87-91.
[14] Brincker R, Zhang L M, Anderson P. Modal identification of output-only systems using frequency domain decomposition [J]. Smart Materials and Structures, 2001, 10(3): 441-455.
[15] 陈刚，吴小辰，柳勇军等. 基于频域分解法和广域稳态量测的低频振荡模式辨识[J]. 电力系统保护与控制, 2011, 39(12): 1-6.
CHEN Gang, WU Xiao-chen, LIU Yong-jun et al. Identification of low-frequency oscillation modes based on frequency domain decomposition method and wide area ambient measurement [J]. Power System Protection and Control, 2011, 39(12): 1-6.
[16] Michel C, Guéguen P, Bard P Y. Dynamic parameters of structures extracted from ambient vibration measurements: An aid for the seismic vulnerability assessment of existing buildings in moderate seismic hazard regions [J]. Soil Dynamics and Earthquake Engineering, 2008, 28(8): 593-604.