弹性纵波在不同非线性法向变形行为节理处的传播

对正向入射弹性纵波穿越具有不同非线性法向变形本构关系的单一岩石干性节理的特性进行理论研究.在没有剪切波的条件下,探讨了BB双曲线模型和经典指数模型两种不同的节理非线性法向变形行为对弹性纵波传播的影响.依据这两类节理本构关系,建立了不同的非线性位移不连续模式,分别获得了弹性纵波穿越单一节理时的反射、透射系数的解析解及数值差分解.针对节理初始法向刚度(kni)、节理闭合量(dn)与最大允许闭合量(dma)比值(γ)以及入射波频率(f)等参数进行研究,同时将2种模型的计算结果进行比较,得到的结论具有一定理论意义.

Transmission of elastic P -wave across single fracture with different nonlinear normal deformation behaviors

A theo retical study w as presented o n the no rmally incident elastic P-w ave t ransmission acro ss sing le dry f racture wi th di fferent no nlinea r no rmal defo rmation behaviors. Wi thout the mix ture of shea r behavio r, the BB hyperbolic elastic model a nd classical exponentia l elastic model was used to inv estigate the effect s o f nonlinear normal defo rmatio n o n P-wav e no rmal incidence. Based on these nonlinear models, the dif ferent nonlinear displacement di scontinui ty models w ere established. The analy tic resolutio n and numerica l di fference resolution o f reflected and t ransmit ted coef ficients fo r no rmally incident P-wav e propaga tes across sing le f racture wi th dif ferent nonlinear normal defo rmatio n behav io rs w ere o btained. Parametric studies w ere conducted in terms o f f racture ini tial no rmal sti ffness (k ni ) , the quanti ta tiv e ratio (V) of the f racture current maximum closure (dn ) to the f racture maximum allow able clo sure (dma ) and the incident w ave f requency ( f ) . Compari so ns betw een the result s o f dif ferent no nlinear behavio rs w ere made, reading v ery impo rtant the co nclusions.