基于饱和砂性土地基动孔压比变化对地基刚度的影响规律，本文通过控制输入地震动持时压缩比和强度的方法，提出了变刚度地基上隔震结构振动台模型试验方法，并结合已完成的不同地基上土-桩-隔震结构系列振动台模型试验，分析了地基刚度变化对基础隔震结构动力学特性的影响规律。结果表明：随着结构-土体相对刚度比的增大，变刚度地基上基础隔震结构一阶自振频率降低，但体系阻尼比明显增大，尤其是隔震层的隔震效率发生了明显的降低。变刚度地基上结构-土体相对刚度比显著影响隔震结构楼层加速度反应和层间位移反应，强震下结构-土体相对刚度比越大，隔震结构楼层加速度反应和层间位移反应较刚性地基时增大越显著。基于系列振动台模型试验结果，本文初步给出了基于结构-土体相对刚度比的小高宽比隔震结构模型周期延长率、阻尼比、层间位移角SSI影响率以及隔震层位移SSI影响率的预测公式，本文的研究结果有助于推动结构隔震技术的更广泛应用。
Abstract
Based on the influence law of dynamic pore pressure ratio changing on the stiffness of saturated sandy soil foundation, this paper proposes a novel and efficient shaking table model test method for the base-isolated structures on the variable stiffness foundation by controlling the time-holding compression ratio and intensity of the input ground motion. Besides, the influence law of the foundation stiffness on the dynamic characteristics of the base-isolation structure is also analyzed by combining with previous completed shaking table model tests of soil-pile-isolated structures on different foundations. The results indicate that the first-order natural vibration frequency of the base-isolation structure on variable stiffness foundation reduces with the increase of the relative stiffness ratio of structure to soil foundation. However, the damping ratio of the interaction system rises obviously, especially the isolation efficiency of the isolation layer decreases dramatically. The relative stiffness ratio of structure to soil significantly affects the floor acceleration response and interstorey displacement response of isolated structures. Compared with the rigid foundation, the larger the relative stiffness ratio of structure to soil is under strong earthquake, the more remarkable the floor acceleration response and interstorey displacement response of isolated structures are. Based on a series of shaking table model test results, the prediction formulas for the period extension rate, damping ratio, SSI influence rate of inter-storey drift angle, and SSI influence rate of displacement of isolation layer of isolated structure model with the small height-width ratio based on the relative stiffness ratio of structure to soil are preliminarily given in this paper. The research results of this paper can contribute to promote the more extensive application of structural vibration isolation technology.
Key words: Variable stiffness foundation; Base-isolated structure; Shaking table test; Dynamic characteristics; Isolation efficiency
关键词
变刚度地基 /
基础隔震结构 /
振动台试验 /
动力学特性 /
隔震效率
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Key words
Variable stiffness foundation /
Base-isolated structure /
Shaking table test /
Dynamic characteristics /
Isolation efficiency
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参考文献
[1] Athanasios A. Markou1, George D. Manolis. A fractional derivative Zener model for the numerical simulation of base isolated structures [J]. Bulletin of Earthquake Engineering, 2016, 14:283–295.
[2] Mojtaba Fathi, Akbar Makhdoumi, Mehdi Parvizi. Effect of Supplemental Damping on Seismic Response of Base Isolated Frames under Near & Far Field Accelerations [J]. KSCE Journal of Civil Engineering, 2015,19(5):1359–1365.
[3] Fabio Mazza. Nonlinear incremental analysis of fire-damaged r.c. base-isolated structures subjected to near-fault ground motions [J]. Soil Dynamics and Earthquake Engineering, 2015, 77: 192–202.
[4] 日本建筑学会著.隔震结构设计[M].刘文光,译. 北京: 地震出版社, 2006.
Architectural Institute of Japan.Recommendation for the design of base isolated buildings[M].Translated by Liu Wenguan. Beijing:Earthquake Press,2006.
[5] Wolf J.P. Dynamic Soil-structure Interaction Prentice Hall[M] , Englewood Chifs, NJ, 1985.
[6] Luco.J.E.Wong.L. Seismic response of foundations embedded in a layered half-space[J]. Earthquake Engineering and Structural Dynamics,1987;15(2):233-247.
[7] Zhuang Haiyang, Yu Xu, Zhu Chao, et al.. Shaking table tests for the seismic response of a base-isolated structure with the SSI effect [J]. Soil Dynamics and Earthquake Engineering, 2014, 67(6): 208-218.
[8] 于旭. 考虑土与结构相互作用的隔震结构体系性能研究[D]. 南京工业大学, 2009
Yu Xu. Performance Research on Seismic Isolated Structure System Considering Soil-Structure Dynamic Interaction[D]. Nanjing University of Technology,2009.
[9] 于旭,宰金珉,王志华.铅芯橡胶支座隔震钢框架结构体系振动台模型试验研究[J].世界地震工程，2010，26（03）：30-36.
Yu Xu,Zai Jinming,Wang Zhi hua.Shaking table tests on the model of a steel-framed structure system with lead core rubber bearing isolations[J].World Earthquake Engineering, 2010，26（03）：30-36.
[10] 李昌平, 刘伟庆, 王曙光等. 软土地基上高层隔震结构模型振动台试验研究[J]. 建筑结构学报, 2013, 34(7): 72-78.
Li Changping,Liu Weiqing,Wang Shuguang,et al.Shaking table test on high-rise isolated strucure on soft soil foundation[J].Journal of Building Structures.2013, 34(7): 72-78.
[11] 许成顺, 豆鹏飞, 高畄成等. 地震动持时压缩比对可液化地基地震反应影响的振动台试验[J]. 岩土力学, 2019, 40(1): 147-155.
Xu Cheng-shun, Dou Peng-fei, Gao Liu-cheng, et al. Shaking table test on effects of ground motion duration compression ratio on seismic response of liquefied foundation[J]. Rock and Soil Mechanics, 2019, 40(1): 147-155.
[12] Tso W, Zhu T, Heidebrecht A. Engineering implication of ground motion A/V ratio [J]. Soil Dynamics and Earthquake Engineering, 1992, 11(3): 133-144.
[13] 周燕国,沈 涛,王 越等.基督城易液化场地震后小应变剪切刚度演化规律研究[J]. 岩土工程学报, 2020, 42(8): 1411-1417.
Zhou Yan-guo, Shen Tao, Wang Yue, et al. Post-earthquake evolution of small-strain shear stiffness at liquefiable deposit in Christchurch[J]. Chinese Journal of Geotechnical Engineering, 2019, 40(1): 147-155.
[14] 叶斌，叶冠林，张锋.液化砂土地基刚度恢复过程的振动台试验[J].水利学报, 2012, 43(7): 877-882.
Ye Bin，Ye Guan-lin，Zhang Feng. Shaking-table tests on the stiffness recovery process of liquefied sandy ground[J]. Shuili Xuebao. 2012, 43(7): 877-882.
[15] 李昌平,刘伟庆等. 土-隔震结构相互作用体系动力特性参数的简化分析方法[J].工程力学, 2013,30(07):173-179.
Li Changping, LIU Wei-qing, et al..Simplified method for calculation dynamic characteristics of soil-isolated structure system[J]. Engineering Mechanics, 2013,30(07):173-179.
[16] 于旭,庄海洋,朱超.考虑SSI效应的隔震结构体系简化分析方法[J].地震工程与工程震动. 2014,34(06):192-199.
Yu Xu, Zhuang Haiyang, Zhu Chao. Simplified calculate method for isolated structure system with the dynamic soil-structure interaction[J]. .Earthquake Engineering and Engineering Vibration. 2014,34(06):192-199.
[17] Zhuang Haiyang, Fu Jisai, Yu Xu, et al. Earthquake responses of a base-isolated structure on a multi-layered soft soil foundation by using shaking table tests [J]. Engineering Structures, 2019,179:79-91
[18] 朱超. 软弱地基上桩基基础隔震结构动力特性研究[D]. 南京工业大学, 2015
Zhu Chao. Study of dynamic characteristics of pile base isolation structure on soft ground[D]. Nanjing University of Technology,2015.
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