简介：基于连续统的有限变丑理论和poroelastic理论，为在自然、起始的坐标的浸透液体的多孔的媒介(FSPM)的acoustoelastic理论被开发在波浪速度上调查有效压力和液体毛孔压力的影响。第一，在FSPM的大部分静态的变丑前上附加的一个小动态运动的假设产出自然、起始、最后的配置，谁的排水量，紧张，和压力稳固骨骼并且在一个FSPM粒子的液体能分别地在自然、起始的坐标被描述。第二，从运动和FSPM的非线性的组成的关系的介绍的最后状态的方程的平衡的起始状态的方程的减法为小动态运动导致运动的方程。第三，同类的变丑前的考虑和小动态运动的飞机泛音形式给一个acoustoelastic方程，它为快纵的波浪的关系提供分析明确的表达，快砍波浪，慢砍波浪，并且有稳固骨骼的压力和液体毛孔压力的慢纵的波浪。最后，在靠近毛孔的jacketed条件，开毛孔的jacketed条件，传统的unjacketed条件，和triaxial状况下面的各向同性的FSPM作为一个例子被拿讨论速度快并且慢砍沿着起始的主要稳固骨骼的紧张之一的方向宣传的波浪。详细讨论证明FSPM的波浪速度被有效压力和液体毛孔压力通常影响。仅仅，液体毛孔压力在FSPM的波浪速度上有小效果应用起始的主管的部件稳固骨骼强调或紧张是相等的，它与以前的试验性的结果一致。

简介：Basedonapproximatetheoreticalanalysesonatypiealsphericalcellcontainingasphericalmicrovoid,theinfluencesofmatrixmaterials’microscopicscaleonthemacroscopicconstitutivepotentialthe-oryofporousmaterialandmicrovoidgrowthhavebeeninvestigatedindetail.Byassumingthattheplasticde-formationbehaviorofmatrixmaterialsfollowsthestraingradient(SG)plastictheoryinvolvingthestretchandrotationgradients,theratio(λ=l/a)ofthematrixmaterials’intrinsiccharacteristicLengthltothemicro-voidradiusaisintrodncedintotheplasticconstitutivepotentialandthevoidgrrothlaw.Thepresentresultsindicatethat,whentheradiusaofmicrovoidsiscomparablewiththeintrinsiccharacteristiclengthlofthematrixmaterials,theinfluenceofmicroscopicsizeeffectonneithertheconstitutivepotentialnorthemicro-voidevolutionpredictedcanheignored.Andwhenthevoidradiusaismuchlagerthantheintrinsiccharac-teristiclengthlofthematrixmaterials,thepresentmodelcanretrogressautomaticallytotheimprovedGur-sonmodelthattakesintoaccountthestrainhardeningeffectofmatrixmaterials.

简介：Basedonthetheoryofporousmedia,ageneralGurtinvariationalprinciplefortheinitialboundaryvalueproblemofdynamicalresponseoffluid-saturatedelasticporousmediaisdevelopedbyassuminginfinitesimaldeformationandincompressibleconstituentsofthesolidandfluidphase.Thefiniteelementformulationbasedonthisvariationalprincipleisalsoderived.Asthefunctionalofthevariationalprincipleisaspatialintegraloftheconvolutionformulation,thegeneralfiniteelementdiscretizationinspaceresultsinsymmetricaldifferential-integralequationsinthetimedomain.Insomesituations,thedifferential-integralequationscanbereducedtosym-metricaldifferentialequationsand,asanumericalexample,itisemployedtoanalyzethereflectionofone-dimensionallongitudinalwaveinafluid-saturatedporoussolid.Thenumericalresultscanprovidefurtherunderstandingofthewavepropagationinporousmedia.

简介：Basedontheporousmediatheoryandbytakingintoaccounttheeffectsoftheporefluidviscidity,energyexchangesduetotheadditionalthermalconductionandconvectionbetweensolidandfluidphases,amathematicalmodelforthedynamic-thermo-hydro-mechanicalcouplingofanon-localthermalequilibriumfluid-saturatedporousmedium,inwhichthetwoconstituentsareassumedtobeincompressibleandimmiscible,isestablishedundertheassumptionofsmalldeformationofthesolidphase,smallvelocityofthefluidphaseandsmalltemperaturechangesofthetwoconstituents.Themathematicalmodelofalocalthermalequilibriumfluid-saturatedporousmediumcanbeobtaineddirectlyfromtheaboveone.SeveralGurtin-typevariationalprinciples,especiallyHu-Washizutypevariationalprinciples,fortheinitialboundaryvalueproblemsofdynamicandquasi-staticresponsesarepresented.Itshouldbepointedoutthatthesevariationalprinciplescanbedegeneratedeasilyintothecaseofisothermalincompressiblefluid-saturatedelasticporousmedia,whichhavebeendiscussedpreviously.