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    复杂艰险构造区铁路桥梁系统地震响应分析Part Ⅰ: 断层效应影响

    陈令坤 王璐 翟晨程 陈雯昕 朱利明 王尧周 张清华 张楠 李乔

    陈令坤, 王璐, 翟晨程, 陈雯昕, 朱利明, 王尧周, 张清华, 张楠, 李乔, 2022. 复杂艰险构造区铁路桥梁系统地震响应分析Part Ⅰ: 断层效应影响. 地球科学, 47(3): 867-879. doi: 10.3799/dqkx.2022.019
    引用本文: 陈令坤, 王璐, 翟晨程, 陈雯昕, 朱利明, 王尧周, 张清华, 张楠, 李乔, 2022. 复杂艰险构造区铁路桥梁系统地震响应分析Part Ⅰ: 断层效应影响. 地球科学, 47(3): 867-879. doi: 10.3799/dqkx.2022.019
    Chen Lingkun, Wang Lu, Zhai Chencheng, Chen Wenxin, Zhu Liming, Wang Yaozhou, Zhang Qinghua, Zhang Nan, Li Qiao, 2022. Seismic Response of Railway Bridges in Active Complex Tectonic Zones Part Ⅰ: Effects of Fault Effects. Earth Science, 47(3): 867-879. doi: 10.3799/dqkx.2022.019
    Citation: Chen Lingkun, Wang Lu, Zhai Chencheng, Chen Wenxin, Zhu Liming, Wang Yaozhou, Zhang Qinghua, Zhang Nan, Li Qiao, 2022. Seismic Response of Railway Bridges in Active Complex Tectonic Zones Part Ⅰ: Effects of Fault Effects. Earth Science, 47(3): 867-879. doi: 10.3799/dqkx.2022.019

    复杂艰险构造区铁路桥梁系统地震响应分析Part Ⅰ: 断层效应影响

    doi: 10.3799/dqkx.2022.019
    基金项目: 

    国家重点研发计划“交通基础设施”重点专项 2021YFB2600600

    2018年度江苏省建设系统科技项目——江苏省防灾减灾抗震“四新”技术专题研究 2018ZD039

    高速铁路基础研究联合基金项目 U1934207

    轨道交通安全教育部重点实验室2019年开放基金项目 2019JZZ01

    湖南创新型省份建设专项经费资助项目 2019RS3009

    国家自然科学基金项目 52178180

    国家自然科学基金项目 51878561

    湖南创新型省份建设专项 2019RS3009

    中南大学创新驱动项目 502501006

    详细信息
      作者简介:

      陈令坤(1974-),男,副教授,博士,硕导,主要从事车桥耦合振动研究.ORCID: 0000-0002-8262-2422. E-mail:lkchen@swjtu.edu.cn

    • 中图分类号: P642

    Seismic Response of Railway Bridges in Active Complex Tectonic Zones Part Ⅰ: Effects of Fault Effects

    • 摘要:

      近断层地震对桥梁的影响日益引起关注.本研究提出了桥梁‒土‒桩基全局建模方法,强调了更详细的桥墩及土壤非线性的真正好处,它可以比一系列轴载更真实地描述物理现象.协同SHAKE91程序并利用p-y曲线、t-z曲线和q-z曲线建立土‒桩基非线性模型,采用双线性模型模拟桥墩及桩基础的滞回特性,建立不良地质发育区铁路桥梁‒土‒桩基多跨简支梁桥体系模型,计算其弹塑性地震响应,分析Ap/vp等对桥梁的弹塑性地震响应的影响.研究结果表明:桥梁横竖向响应受Ap/vp影响特点不同,相比墩底固结工况,考虑桩基后桥梁横向地震响应减小;对于竖向响应,在Ap/vp > 10时桥梁竖向地震响应降低,说明竖向地震在较高频率影响桥梁地震响应.

       

    • 图  1  G/Gmax-lgγβ-lgγ曲线

      Fig.  1.  G/Gmax-lgγ curves and β-lgγ curves

      图  2  列车‒桥梁‒桩基计算模型

      a. 3D桩土模型;b. 非线性p-y单元

      Fig.  2.  Model of train-bridge-foundation system

      图  3  考虑桩土的列车‒桥梁系统简图

      a. 桥梁-桩基模型示意图;b. 桩基础立面图(单位m);c. 桩基础平面图(单位mm)

      Fig.  3.  Model of bridges considering SSI

      图  4  桥梁振型图

      a.无SSI横向振型;b.有SSI横向振型

      Fig.  4.  Mode shape of natural vibration of the bridge

      图  5  Japan Kobe 1995地震KJMA/Shin-Osaka波作用下考虑SSI H+V输入桥梁地震响应时程

      Fig.  5.  Seismic responses of bridge subjected to Japan Kobe 1995, KJMA/Shin-Osaka ground motions

      图  6  脉冲/远场地震速度/位移时程曲线

      a.脉冲地震速度时程;b.远场地震速度时程

      Fig.  6.  Velocity/displacement time-history curve under pulse/far field earthquakes

      图  7  近/远场地震下桥梁地震响应峰值与Ap/vp关系

      Fig.  7.  Relationship between Ap/vp and peak seismic response of the bridge under near fault/far field ground motion

      图  8  不考虑/考虑SSI H+V输入工况近远场地震下墩底第1单元转角时程曲线

      a.脉冲地震;b.远场地震

      Fig.  8.  Rotation time-history curve at the first element of the pier base subjected to the near-fault/far field horizontal and vertical ground motions without/with the consideration of the SSI

      图  9  脉冲/远场地震下梁体横向加速度傅里叶谱图

      a.脉冲地震塑性;b.远场地震塑性

      Fig.  9.  Fourier spectrum of lateral acceleration at the girder under pulse/far field earthquakes with considering the SSI

      图  10  脉冲(a)/远场地震(b)FN分量傅里叶谱

      Fig.  10.  Fourier spectrum of the FN component of pulse (a) far field (b) earthquakes

      表  1  脉冲近场地震

      Table  1.   Pulse-typed near-fault ground motion database

      地震名称 台站 震级 断层距(km) 场地 Tp
      (s)
      PGAH
      (g)
      PGVH (cm/s) PGAV
      (g)
      $ {\partial }_{PGA} $ Ap/vp
      Kobe 1995 KJMA 6.9 1.0 粘土 1.09 0.854 105.6 0.342 0.401 8.08
      Northridge 1994 Rinaadi 6.7 0.0 粘土 1.25 0.869 149.0 0.834 0.959 5.84
      Kobe 1995 Takatori 6.9 1.4 粘土 1.55 0.682 153.2 0.271 0.398 4.45
      Imperial Valley 06 1979 Agrarias 6.53 0.6 粘土 2.34 0.311 53.5 0.834 2.679 5.82
      Duzce 1999 Bolu 7.1 6.6 粘土 5.94 0.775 65.8 0.202 0.261 11.79
      Chi-Chi 1999 TCU059 7.62 3.6 粘土 7.78 0.168 64.1 0.056 0.334 2.63
      注:Tp为脉冲周期;PGAH为横向峰值地震加速度;PGVH为横向峰值地震速度;PGAV为竖向峰值地震加速度;竖向峰值地震加速度与横向峰值地震加速度比值$ {\partial }_{PGA}=PG{A}_{\mathrm{V}}/PG{A}_{\mathrm{H}} $;Ap/vp是横向峰值加速度与横向峰值速度的比值.
      下载: 导出CSV

      表  2  远场地震

      Table  2.   Far-field ground motion database

      地震名称 台站 震级 断层(km) 场地 PGAH
      (g)
      PGVH (cm/s) PGAV
      (g)
      $ {\partial }_{PGA} $ Ap/vp
      Chi-Chi 1999 CHY036 7.6 16.1 粘土 0.322 36.31 0.104 0.322 8.89
      Kobe 1995 Shin-Osaka 6.9 19.2 粘土 0.186 29.96 0.058 0.314 6.23
      Imperial Valley 1979 El Centro Array #13 6.5 21.9 粘土 0.138 14.23 0.045 0.330 9.70
      Loma Prieta 1989 Coyote Lake Dam (Downst) 6.9 20.8 粘土 0.159 10.30 0.0947 0.593 15.50
      Chi-Chi 1999 CHY092 7.6 22.7 粘土 0.111 60.71 0.119 1.076 1.83
      Loma Prieta 1989 Capitola 6.9 15.2 粘土 0.371 34.55 0.541 1.455 10.75
      下载: 导出CSV

      表  3  桥墩/桩柱弯矩‒曲率骨架曲线响应计算值

      Table  3.   Calculated value of skeleton-frame curves of moment-curvature relation of pier/pile

      地震方向 屈服转角
      (10-3 rad)
      屈服弯矩
      (103 kN·m)
      极限转角
      (10-3 rad)
      极限弯矩
      (103 kN·m)
      桥墩 横桥向 0.47 56.40 17.87 97.9
      顺桥向 1.45 24.80 52.63 35.8
      桩柱 横桥向 2.31 5.05 47.1 6.14
      顺桥向 2.18 5.71 44.3 6.96
      下载: 导出CSV

      表  4  地质参数

      Table  4.   Soil column properties

      层序号 到桩顶距离段(m) 土层厚度(m) 岩土名称 密度
      (g/cm3)
      剪切波速
      (m/s)
      泊松比 剪切模量(MPa) 弹性模量(MPa)
      1 0~3.5 3.5 淤泥、淤泥质土 1.85 85 0.46 13.37 49.47
      2 3.5~11.0 7.5 含淤泥粉砂 1.94 191 0.35 70.77 274.59
      3 11~29 18 全风化花岗片麻岩 2.05 311 0.27 198.28 812.95
      4 29~31 2 强风化花岗片麻岩 2.00 1 200 0.25 2 880 11 250
      5 31~34 3 弱风化花岗片麻岩 2.10 1 500 0.22 4 725 16 601
      下载: 导出CSV

      表  5  脉冲近场地震弹塑性响应峰值

      Table  5.   Peak seismic response of the pulse-typed near-fault ground motions

      地震波 梁跨中竖向位移
      (mm)
      墩底轴力
      (104 kN)
      墩顶横向位移
      (mm)
      墩底剪力
      (104 kN·m)
      墩底弯矩
      (104 kN·m)
      Kobe 1995, KJMA 25.59 1.34 31.30 0.50 6.30
      Northridge01 1994, Rinaadi 21.26 1.37 29.50 0.43 5.96
      Kobe 1995, Takatori 22.00 1.56 28.60 0.52 6.39
      Imperial Valley06 1979, Agrarias 32.58 1.87 23.17 0.34 5.26
      Duzce 1999, Bolu 22.75 1.41 36.24 0.41 6.06
      Chi-Chi 1999, TCU059 21.52 1.37 32.50 0.48 6.37
      下载: 导出CSV

      表  6  远场地震弹塑性响应峰值

      Table  6.   Peak seismic response of the far field-typed ground motions

      地震波 梁跨中竖向位移(mm) 墩底轴力
      (104 kN)
      墩顶横向位移(mm) 墩底剪力
      (104 kN·m)
      墩底弯矩
      (104 kN·m)
      Chi-Chi 1999, CHY036 21.48 1.38 28.66 0.46 6.01
      Kobe 1995, Shin-Osaka 26.09 1.37 22.98 0.42 5.99
      Imperial Valley 1979, El Centro Array #13 23.31 1.39 20.06 0.21 3.05
      Loma Prieta 1989, Coyote Lake Dam (Downst) 25.20 1.47 19.95 0.32 3.54
      Chi-Chi 1999, CHY092 23.08 1.38 32.14 0.47 6.17
      Loma Prieta 1989, Capitola 32.71 1.99 29.23 0.49 6.19
      下载: 导出CSV
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    • 收稿日期:  2021-11-17
    • 刊出日期:  2022-03-25

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