The Influence of Air Concentration on the Propagation Characteristics of Compressional Waves in Different Nearly Saturated Soils
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摘要: 基于饱和两相介质波动的土力学模型，借助均匀孔隙流体的概念，推导了准饱和土中弹性波波速和衰减系数的理论解析表达式。通过数值计算，系统分析了含气量对4类不同典型准饱和土中压缩波传播特性的影响，全面讨论了不同含气量的准饱和土中压缩波的频散和衰减特性，并与气饱和土、水饱和土的计算结果进行比较。结果表明，不同准饱和土中压缩波速度和衰减随含气量变化的形状相同，但幅值不同；随着含气量增加，P1波波速减小，气饱和土中达到最小，且频散现象愈加不明显，原因在于气-固耦合作用显著低于水-固耦合作用；但高频时，P2波速在气饱和土中取到最大值。总之，含气量对压缩波传播特性的影响非常显著，且结论对认识地震波传播特性及工程结构抗震设防有重要的理论和实践意义。Abstract: Based on the soil mechanics model in the saturated two-phase medium, the analytical expressions for the velocity and attenuation coefficient of elastic waves in the nearly saturated soil are derived using the concept of homogeneous pore fluid. Through numerical calculations, the influence of air concentration on the propagation characteristics of compressional waves in four different nearly saturated soils was systematically analyzed, and the dispersed and attenuated characteristics of compressional waves in the nearly saturated soils with varying concentrations of air were comprehensively discussed and compared with the results of air-saturated and water-saturated soils. The results show that the shapes of compressional wave velocity and attenuation coefficients in different nearly saturated soils are the same, but the amplitudes differ. As the air concentration increases, the velocity of P1-wave decreases and reaches the minimum value in the air-saturated soil. The dispersion phenomenon becomes less obvious, the reason is that the air-solid coupling effect is significantly lower than the water-solid coupling effect. While at high frequencies, the velocity of the P2 wave reaches its maximum value in air-saturated soil. All in all, the influence of air concentration on the propagation characteristics of compressional waves is very significant. The conclusions in this article are of great theoretical and practical significance for understanding the propagation characteristics of seismic waves and seismic fortification of engineering structures.
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图 1 不同绝对孔隙压力下含气量与孔隙流体体积模量的关系
Figure 1. Bulk modulus of pore fluid versus air concentration for different absolute pressure
图 2 4种准饱和土中压缩波波速、衰减与含气量的关系
Figure 2. Effect of air concentration on the velocities and attenuation of compression waves in four nearly saturated soils
图 3 水饱和、气饱和及准饱和土中压缩波速度弥散及衰减曲线
Figure 3. Attenuated and dispersive cures of compression waves in water, gas-saturated and nearly saturated soils
表 1 不同土体的材料参数
Table 1. Physical mechanical parameters of different soils
材料 ρs /(kg.m−3) ρw/ (kg.m−3) n k/(m3·s/kg) λ/Pa μ/Pa Ew/Pa Pa/Pa 卵石土 2.15×103 1.0×103 0.4 3.24×10−7 4.403×108 8.547×108 1.85×109 1.0×105 砂土 2.1×103 1.0×103 0.4 4.6×10−8 3.0×108 2.778×108 1.85×109 1.0×105 粉土 1.97×103 1.0×103 0.594 5.79×10−10 9.623×107 6.415×107 1.85×109 1.0×105 淤泥质黏土 1.7×103 1.0×103 0.625 6.0×10−14 1.14×108 2.17×107 1.85×109 1.0×105 
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表 2 水饱和及气饱和土的材料参数
Table 2. Physical mechanical parameters of water- and gas-saturated soils
材料 ρs/(kg.m−3) ρw/(kg.m−3) n k/(m3·s/kg) λ/Pa μ/Pa Ew/Pa Pa/Pa 水饱和土 2.65×103 1.0×103 0.27 1.0×10−7 2.61×107 2.61×107 2.0×109 1.0×105 气饱和土 2.65×103 1.2 0.27 5.6×10−6 2.61×107 2.61×107 1.3×105 1.0×105
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蔡袁强, 李保忠, 2006. 饱和度变化对弹性波在非饱和砂岩表面反射和透射的影响. 岩石力学与工程学报, 25(3): 520−527.Cai Y. Q., Li B. Z., 2006. Effect of water saturation on reflection and transmission of elastic waves at interface of partially saturated sandstone. Chinese Journal of Rock Mechanics and Engineering, 25(3): 520−527. (in Chinese) 陈少林, 廖振鹏, 2002. 关于两相介质动力学问题建模的注记. 地震工程与工程振动, 22(4): 1−8.Chen S. L., Liao Z. P., 2002. Study on mechanic models of two-phase media. Earthquake Engineering and Engineering Vibration, 22(4): 1−8. (in Chinese) 李保忠, 蔡袁强, 2003. 饱和度对横观各向同性准饱和多孔介质中弹性波传播的影响. 水利学报, (9): 94−101.Li B. Z., Cai Y. Q., 2003. Influence of water saturation on elastic wave propagation in transversely isotropic quasi-saturated porous media. Journal of Hydraulic Engineering, (9): 94−101. (in Chinese) 李伟华, 2002. 饱和度对波在土层交界面的反射、透射系数的影响. 西北地震学报, 24(4): 303−309.Li W. H., 2002. Influence of water saturation on seismic reflection and transmission coefficients at a mainly water-saturated porous soil interface. Northwestern Seismological Journal, 24(4): 303−309. (in Chinese) 门福录, 1981. 波在饱含流体的孔隙介质中的传播问题. 地球物理学报, 24(1): 65−76.Men F. L., 1981. Problems of wave propagation in porous, fluid-saturated media. Acta Geophysica Sinica, 24(1): 65−76. (in Chinese) 仇浩淼, 夏唐代, 何绍衡等, 2018. 流体/准饱和多孔介质中伪Scholte波的传播特性. 物理学报, 67(20): 204302. doi: 10.7498/aps.67.20180853Qiu H. S., Xia T. D., He S. H., et al., 2018. Propagation characteristics of pseudo-Scholte waves at the interface between finite-thickness fluid layer and quasi-saturated porous half-space. Acta Physica Sinica, 67(20): 204302. (in Chinese) doi: 10.7498/aps.67.20180853 夏唐代, 周新民, 2006. 气饱和土中弹性波的传播特性. 江南大学学报(自然科学版), 5(6): 711−714, 720.Xia T. D., Zhou X. M., 2006. Propagation Characteristics of elastic plane waves in air-saturated soils. Journal of Southern Yangtze University (Natural Science Edition), 5(6): 711−714,720. (in Chinese) 夏唐代, 薛威, 颜可珍, 2007. 准饱和土中的瑞利波弥散特性. 江南大学学报(自然科学版), 6(1): 76−80. doi: 10.3969/j.issn.1671-7147.2007.01.019Xia T. D., Xue W., Yan K. Z., 2007. Dispersion of Rayleigh wave in a nearly saturated soil. Journal of Southern Yangtze University (Natural Science Edition), 6(1): 76−80. (in Chinese) doi: 10.3969/j.issn.1671-7147.2007.01.019 肖萌, 崔杰, 李亚东等, 2023. 海洋场地Rayleigh波传播特性及其影响因素分析. 湖南大学学报(自然科学版), 50(5): 191−203. doi: 10.16339/j.cnki.hdxbzkb.2023069Xiao M., Cui J., Li Y. D., et al., 2023. Analysis on propagation characteristics of Rayleigh waves in ocean sites and their influence parameters. Journal of Hunan University (Natural Sciences), 50(5): 191−203. (in Chinese) doi: 10.16339/j.cnki.hdxbzkb.2023069 徐长节, 史焱永, 2004. 非饱和土中波的传播特性. 岩土力学, 25(3): 354−358.Xu C. J., Shi Y. Y., 2004. Characteristics of wave propagation in unsaturated soils. Rock and Soil Mechanics, 25(3): 354−358. (in Chinese) 徐长节, 马晓华, 蔡袁强, 2005. 粘弹性准饱水岩层中地震波的传播. 岩石力学与工程学报, 24(14): 2490−2496.Xu C. J., Ma X. H., Cai Y. Q., 2005. Seismic wave propagation in viscoelastic and nearly saturated rock. Chinese Journal of Rock Mechanics and Engineering, 24(14): 2490−2496. (in Chinese) 徐平, 夏唐代, 2008. 饱和度对准饱和土体中瑞利波传播特性的影响. 振动与冲击, 27(4): 10−13. doi: 10.3969/j.issn.1000-3835.2008.04.004Xu P., Xia T. D., 2008. Influence of saturation degree on propagation characteristics of Rayleigh waves in nearly saturated soils. Journal of Vibration and Shock, 27(4): 10−13. (in Chinese) doi: 10.3969/j.issn.1000-3835.2008.04.004 周新民, 2006. 准饱和土波动特性及动力响应研究. 杭州: 浙江大学, 45−62.Zhou X. M. , 2006. Research on wave propagation characteristics and dynamic response in partially saturated soils. Hangzhou: Zhejiang University, 45−62. (in Chinese) 周新民, 夏唐代, 2007. 半空间准饱和土中瑞利波的传播特性研究. 岩土工程学报, 29(5): 750−754.Zhou X. M., Xia T. D., 2007. Characteristics of Rayleigh waves in half-space of partially saturated soil. Chinese Journal of Geotechnical Engineering, 29(5): 750−754. (in Chinese) 周新民, 刘真, 夏唐代等, 2009. 准饱和土特性对地震波的传播影响分析. 见: 第三届全国岩土与工程学术大会论文集. 成都: 中国地质学会工程地质专业委员会, 中国岩石力学与工程学会, 中国建筑学会工程勘察分会, 中国土木工程学会土力学及岩土工程分会, 736−739. Bardet J. P., Sayed H., 1993. Velocity and attenuation of compressional waves in nearly saturated soils. Soil Dynamics and Earthquake Engineering, 12(7): 391−401. doi: 10.1016/0267-7261(93)90002-9 Gu X. Q., Zuo K. L., Tessari A., et al., 2021. Effect of saturation on the characteristics of P-wave and S-wave propagation in nearly saturated soils using bender elements. Soil Dynamics and Earthquake Engineering, 145: 106742. doi: 10.1016/j.soildyn.2021.106742 Song J., Xu C. S., Li L., 2021. The influence of permeability on the propagation characteristics of the waves in different saturated soils. Applied Sciences, 11(17): 8138. doi: 10.3390/app11178138 Vardoulakis I., Beskos D. E., 1986. Dynamic behavior of nearly saturated porous media. Mechanics of Materials, 5(1): 87−108. doi: 10.1016/0167-6636(86)90017-7 Verruijt A. , 1969. Elastic storage of aquifers. In: De Wiest R. J. M. , ed. , Flow Through Porous Media. New York: Academic Press, 331−376. Yang J., Sato T., 2000a. Effects of pore-water saturation on seismic reflection and transmission from a boundary of porous soils. Bulletin of the Seismological Society of America, 90(5): 1313−1317. doi: 10.1785/0120000008 Yang J., Sato T., 2000b. Influence of water saturation on horizontal and vertical motion at a porous soil interface induced by incident SV wave. Soil Dynamics and Earthquake Engineering, 19(5): 339−346. doi: 10.1016/S0267-7261(00)00023-3 Yang J., 2002. Saturation effects of soils on ground motion at free surface due to incident SV waves. Journal of Engineering Mechanics, 128(12): 1295−1303. doi: 10.1061/(ASCE)0733-9399(2002)128:12(1295) Zhang B., Chen X. L., Qiu L. J., et al., 2023. Characteristics of elastic wave propagation in fluid-saturated porous media based on the model of soil mechanics. Pure and Applied Geophysics, 180(6): 2309−2326. doi: 10.1007/s00024-023-03269-z -
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