基于 g-λ 模型的充填节理中P波传播规律分析

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CHAI Shaobo'，WEN Chengwu'，SONG Lang²，XU Yinglong （1.School of Civil Engineering，Chang’an University，Xi’an 71OO64，China; 2. City College，Xi'an Jiaotong University，Xi’an 710O18，China）

Abstract The propagation law of stress waves in joints，as weak structural planes in rock mases，plays a pivotal role in assessing the dynamic stability of rock mass.In particular，the wave propagation characteristics become complicated in filled joints due to their thickness and the properties of the filling materials.Current theoretical investigations on wave propagation in filled rock joints remain scarce，with insufficient consideration of nonlinear deformation characteristics at contact interfaces. Therefore，this paper adopts the g λ model to characterize nonlinear normal deformation behavior at filled joint interfaces.Taking into account the influence of the filling layer，the propagation equation of stress waves in filled joints is established by the improved timedomain recursive analysis method. Moreover，a parametric analysis is conducted on the transmission and reflection coefficients of ΔP waves.Through theoretical analysis，it is found that the parameter λ is related to the cohesion and internal friction angle of the joints，with increasing λ amplifying nonlinear stiffness enhancement rates.The transmisson and reflection coefficients of stress waves are quite sensitive to changes in the incident angle.As the incident angle increases，the reflection coefficient of ΔP waves first decreases and then increases. The transmission coefficient of ΔP waves remains relatively stable as the incident angle increases，but drops sharplywhen the incident angle continues to increase.Overall，changes in the initial normal stiffess of the joint have a significant impact on the transmission and reflection coeficients of P waves，while changes in the tangential of the joint have dominant influence on the transmissionand reflection coefficients of S waves.The results provide a theoretical basis for the propagation law of stress waves in the rock masses with filled joints. Keywordsstress wave; filled joint; g -入 model； propagation equations ； transmission and reflection coefficients

天然岩体并非均质体，其中存在大量的节理[1]，岩体会因为节理的存在而表现出不连续性和不均匀性。（剩余12906字）