饱和散体的分形行为与振动液化
详细信息 本馆镜像全文    |  推荐本文 | | 获取馆网全文
摘要
饱和散体结构复杂 ,在振动作用下会发生液化现象。利用分形几何学分析得出散体粒度分布、孔隙分布和颗粒比表面积都具有分形特征 ,服从标度律。振动过程中 ,时间序列、功率谱密度、振动脉冲积分分布、时间序列的自相关函数均服从幂律关系 ,具有分形特征。振动液化的稳态发展过程服从幂律 ,在振动过程中显示出自组织临界性 ,随着循环次数达到一定程度 ,饱和散体应力急剧减小或完全丧失 ,应变急剧增加 ,已不能再承受荷载 ,出现“雪崩”现象。
Saturated granules have a complicated structure and liquefaction will take place by the effect of vibration. The authors analyse their size distribution, pore distribution and specific surface area by means of fractal geometry, coming to the conclusion that they all have fractal characteristics and obey the scaling law. In the course of vibration, time series, power spectral density, integral distribution of vibration pulse and autocorrelation functions of time series all obey the power law and have fractal characteristics. The steady development process of vibration liqufaction obeys the power law. In the course of vibration, self-organizing criticality is displayed. With increasing recurrence number the stress of saturated granules will decrease or disappear completely and the strain will ncrease rapidly, so that the granules can not sustain load, resulting to "avalanche".
引文
[1] 洪毓康.土质与土力学.北京:人民交通出版社,2000
    [2] 特科特DL .分形与混沌.北京:地震出版社,1993
    [3] 傅鹤林,李 亮,李 磊.膨胀土结构分形特征研究.长沙铁道学院学报,2000,18(1):1~5
    [4] TurcotteDL .FractalsandFragmentation.JGeophysRes,1986,91:1921~1926
    [5] 徐永富,孙婉莹,吴正根.我国膨胀土的分形结构的研究.河海大学学报,1997,25(1):18~23
    [6] BarkP ,TangC ,WiesenfeldK .Self organizedcriticality.PhysRev,1988,A38:364~374
    [7] 龙期威.金属中的分形与复杂性.上海:上海科学技术出版社,1999
    [8] 谢和平.岩土介质的分形孔隙与分形粒子.力学进展,1993,23(2):145~164
    [9] PetriA ,PaparoG ,VespingnaniA ,etal.Experimentalevidenceforcrit icaldynamicsinmicrofacturingprocesses.PhysRevLett,1994,73(25):3423~3426
    [10] OchiaiM ,OzaoR ,YamazakiY .Self similaritylawofparticlesizedis tributionandenergylawinsizereductionofsolids.PhysicaA ,1992,191:295~300
    [11] 吴爱祥.振动场中矿岩散体特性与动力学理论研究:[博士学位论文].长沙:中南工业大学,1991

版权所有:© 2023 中国地质图书馆 中国地质调查局地学文献中心