下卧饱和半空间粘弹性土层上基础阻抗函数的分析
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摘要
由于地下水的影响,实际土层一般由含水土层和不含水土层组成。由于求解的复杂性,目前基础阻抗函数的求解中很少考虑这种地基情形。根据干土是饱和土的特殊情形这一事实,通过将液相压缩模量、孔隙比以及惯性耦合质量密度取为零,可以使干土的动力反应统一到饱和土动力反应求解方案中,从而可通过饱和地基上基础阻抗函数的一种求解方法,解决饱和土和干土并存时基础阻抗函数的求解问题。地基无限域的影响通过局部透射人工边界考虑。通过算例验证了该方法的可行性,并考察了干土层厚度以及基础埋深对动力阻抗的影响。
In general,the soil stratum consists of two-phase saturated poroelastic zones and single-phase viscoelastic zones duo to ground water.In most cases of dynamic impedance analysis,the soil has been assumed to be a viscoelastic or saturated medium.Little attention has been paid to the analysis of foundation on stratum consisting viscoelastic and saturated soil.Based on the fact that single-phase soil is a special case of two-phase saturated soil,the dynamic analysis of single-phase soil can be unified into the analysis of saturated soil by setting the bulk modulus of pore fluid,porosity and the coupling mass density to be zero.Thus,the dynamic impedance of foundations on viscoelastic and saturated stratum can be analyzed by a method for saturated medium case.The technique is applied to the computation of the dynamic impedance of rectangular foundations on viscoelastic and saturated stratum.The effect of dry soil thickness and the embedded depth of foundation on the dynamic impedance are examined.
In general,the soil stratum consists of two-phase saturated poroelastic zones and single-phase viscoelastic zones duo to ground water.In most cases of dynamic impedance analysis,the soil has been assumed to be a viscoelastic or saturated medium.Little attention has been paid to the analysis of foundation on stratum consisting viscoelastic and saturated soil.Based on the fact that single-phase soil is a special case of two-phase saturated soil,the dynamic analysis of single-phase soil can be unified into the analysis of saturated soil by setting the bulk modulus of pore fluid,porosity and the coupling mass density to be zero.Thus,the dynamic impedance of foundations on viscoelastic and saturated stratum can be analyzed by a method for saturated medium case.The technique is applied to the computation of the dynamic impedance of rectangular foundations on viscoelastic and saturated stratum.The effect of dry soil thickness and the embedded depth of foundation on the dynamic impedance are examined.
引文
[1]Luco J E,Westmann R A.Dynamic response ofcircular footings[J].Journal of EngineeringMechanics,ASCE,1971,97(5):1 381—1 395.
[2]Veletsos A S,Wei Y T.Lateral and rocking vibrationof footings[J].Journal of Soil Mechanics andFoundation,ACSE,1971,97(5):1 227—1 248.
[3]Wong H L,Luco J E.Dynamic response of rigidfoundation of arbitrarily shape[J].EarthquakeEngineering and Structural Dynamics,1976,4(6):3—16.
[4]Gazetas G,Tassoulas J I.Horizontal stiffness ofarbitrarily shaped embedded foundations[J].Journalof Geotechnical Engineering,ASCE,1987,113(5):440—457.
[5]Halpern M R,Christiano P.Steady-state harmonicresponse of a rigid plate bearing on a liquid-saturatedporoelastic halfspace[J].Earthquake Engineering andStructural Dynamics,1986,14:439—454.
[6]Kassir M K,Xu J.Interaction functions of a rigidstrip bonded to saturated elastic half-space[J].Int.Solids Structures,1988,24(9):915—936.
[7]Bougacha S,Roesser J M,Tassoulas J L.Dynamicstiffness of foundations on fluid-filled poro-elasticstratum[J].Journal of Engineering Mechanics,1993,119(8):1 649—1 662.
[8]Chopra M B,Dargush G F.Boundary element analysisof stresses in an axisymmetric soil mass undergoingconsolidation.[J].Numerical and Analytical Methodsin Geomechanics,1995,19:195—218.
[9]Japon B R,Gallego R,Dominguez J.Dynamicstiffness of foundations on saturated poroelastic soils[J].Journal of Engineering Mechanics,1997,123(11):1 121—1 129.
[10]Jin B,Liu H.Rocking vibration of rigid disk onsaturated poro-elastic medium[J].Soil Dynamic andEarthquake Engineering,2000,19:469—472.
[11]Hu X Q,Cai Y Q,Wang J,et al.Rocking vibrationsof a rigid embedded foundation in a poro-elastic soillayer[J].Soil Dynamic and Earthquake Engineering,2010,30:280—284.
[12]Biot M A.General theory of three-dimensionalconsolidation[J].J.Appl.Phys.,1941,12:155—164.
[13]陈少林,廖振鹏,陈进.两相介质近场波动模拟的一种解藕有限元方法[J].地球物理学报,2005,48(4):909—917.CHEN S L,LIAO Z P,CHEN J.A decoupling FEMfor simulating near-field wave motions in two-phasemedia[J].Chinese J.Ceophys.2005,48(4):909—917.
[14]陈少林,廖振鹏,多次透射公式在衰减波场中的实现[J].地震学报,2003,25(3):272—279.CHEN SHAO-LIN,LIAO ZHEN-PENG.Multi-transmitting formula for attenuating waves[J].ACTASEISMOLOGICA SINICA,2003,25(3):272—279.
[2]Veletsos A S,Wei Y T.Lateral and rocking vibrationof footings[J].Journal of Soil Mechanics andFoundation,ACSE,1971,97(5):1 227—1 248.
[3]Wong H L,Luco J E.Dynamic response of rigidfoundation of arbitrarily shape[J].EarthquakeEngineering and Structural Dynamics,1976,4(6):3—16.
[4]Gazetas G,Tassoulas J I.Horizontal stiffness ofarbitrarily shaped embedded foundations[J].Journalof Geotechnical Engineering,ASCE,1987,113(5):440—457.
[5]Halpern M R,Christiano P.Steady-state harmonicresponse of a rigid plate bearing on a liquid-saturatedporoelastic halfspace[J].Earthquake Engineering andStructural Dynamics,1986,14:439—454.
[6]Kassir M K,Xu J.Interaction functions of a rigidstrip bonded to saturated elastic half-space[J].Int.Solids Structures,1988,24(9):915—936.
[7]Bougacha S,Roesser J M,Tassoulas J L.Dynamicstiffness of foundations on fluid-filled poro-elasticstratum[J].Journal of Engineering Mechanics,1993,119(8):1 649—1 662.
[8]Chopra M B,Dargush G F.Boundary element analysisof stresses in an axisymmetric soil mass undergoingconsolidation.[J].Numerical and Analytical Methodsin Geomechanics,1995,19:195—218.
[9]Japon B R,Gallego R,Dominguez J.Dynamicstiffness of foundations on saturated poroelastic soils[J].Journal of Engineering Mechanics,1997,123(11):1 121—1 129.
[10]Jin B,Liu H.Rocking vibration of rigid disk onsaturated poro-elastic medium[J].Soil Dynamic andEarthquake Engineering,2000,19:469—472.
[11]Hu X Q,Cai Y Q,Wang J,et al.Rocking vibrationsof a rigid embedded foundation in a poro-elastic soillayer[J].Soil Dynamic and Earthquake Engineering,2010,30:280—284.
[12]Biot M A.General theory of three-dimensionalconsolidation[J].J.Appl.Phys.,1941,12:155—164.
[13]陈少林,廖振鹏,陈进.两相介质近场波动模拟的一种解藕有限元方法[J].地球物理学报,2005,48(4):909—917.CHEN S L,LIAO Z P,CHEN J.A decoupling FEMfor simulating near-field wave motions in two-phasemedia[J].Chinese J.Ceophys.2005,48(4):909—917.
[14]陈少林,廖振鹏,多次透射公式在衰减波场中的实现[J].地震学报,2003,25(3):272—279.CHEN SHAO-LIN,LIAO ZHEN-PENG.Multi-transmitting formula for attenuating waves[J].ACTASEISMOLOGICA SINICA,2003,25(3):272—279.
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