涌潮荷载下桩式丁坝的动力响应
详细信息 本馆镜像全文    |  推荐本文 | | 获取馆网全文
摘要
通过势流理论研究了简谐荷载作用下的无黏性流-圆桩-土体系统的动力响应。采用动力Winkler弹性地基梁模型模拟桩与土的相互作用,考虑无黏性流体和桩体的耦合作用,将圆桩散射的特征函数展开,由解析法给出了埋置在土中的圆桩在无黏性流体中的稳态动力响应。最后将实测的钱塘江涌潮冲击荷载用傅立叶变换展开成正余弦荷载。考虑由流体黏性引起的速度力和黏性阻尼的Morison公式的速度力分项,研究分析了涌潮作用下桩式丁坝的受力特性及桩身振动响应。计算结果表明:埋置桩的自振频率较高,而涌潮荷载中高频分量相对较小,所以涌潮下桩式丁坝不易发生共振,工程中可采用静力方法进行设计。
The dynamic response of the water-cylindrical pile-soil system under harmonic load is studied by potential flow theory.The water is assumed as inviscid fluid and the Winkle elastic foundation beam model is applies to simulate the interaction between pile and soil.The coupling between fluid and pile is considered by expanding the eigen-function of the dispersion due to the cylindrical pile.On this basis,the steady dynamic response of the pile inserted in soil under the action of inviscid fluid can be deduced analytically.For verifiying the validity of this analysis result,the in-situ observed impact force acting on a pile due to bore in the Qintang River is expanded into series by means of Fourier transformation to examine the dynamic response of the pile to the velocity force due to fluid viscosity.The velocity force item in Morison formula expressing the viscous damping is taken into account.The calculation result shows that the natural frequency of the pile is high and the high frequency component of the bore load is comparative small,the resonance of pile-groin will not occur.Practically,only the static load should be considered in engineering design.
引文
[1]赵谓军,严盛,宣伟丽,林炳尧.涌潮河口桩式丁坝的护滩保塘效果分析[J].水利学报,2006,37(6):699-703.
    [2]周叮.考虑液面波动和液体压缩时一侧受液作用悬臂梁的横振分析[J].应用力学学报,1994,11(2):106-111.
    [3]张绍文,倪汉根.水中悬壁结构振动与水动力特性研究[J].大连理工大学学报,1996,36(3):329-333.
    [4]Mostafa Y E,Hesham M,Naggar E I.Response of fixed offshore platforms to wave and current loading including soil-structure interaction[J].Soil Dynamic and Earthquake Engineering,2004,(24):357-368.
    [5]刘笑海,王仲捷.结构-波浪-海床耦合系统中大圆筒结构的波压力响应[J].水利学报,2003,(4):67-74.
    [6]邵卫云,毛根海,等.钱塘江涌潮压力的动态观测与分析研究[J].浙江大学学报(工学版),2002,36(3):247-251.
    [7]李远林.波浪理论及波浪荷载[M].广州:华南理工大学出版社,1979.
    [8]袁迎春,赖伟,王君杰,胡世德.Morison方程中动水阻力项对桥梁桩柱地震反应的影响[J].世界地震工程,2005,21(4):88-94.
    [9]Dobry R,Gazetas G.Simple method for dynamic stiffness and damping of floating pile groups[J].Geotechnique,1998,38(4):557-574.
    [10]Makris N,Gazetas G.Displacement phase differences in a harmonically oscillating pile[J].Geotechnique,1993,43(1):135-149.
    [11]赵晖,蔡袁强,宣伟丽,等.双排桩丁坝在涌潮作用下的内力测试和分析[J].人民长江,2005,36(2):37-39.
    [12]蔡袁强,徐长节,袁海明.任意荷载下成层粘弹性地基的一维固结[J].应用数学和力学,2001,22(3):307-313.
    [13]吕江,朱陆明,翟洪刚.涌潮冲击丁坝时涌潮压力初步研究[J].科技通报,2005,21(1):34-40.
    [14]JTJ 213-98,海港水文规范[S].

版权所有:© 2023 中国地质图书馆 中国地质调查局地学文献中心