地震强度递增沙堆模型响应机制的研究
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摘要
针对汶川地震Ⅹ度和Ⅺ度烈度区崩塌滑坡面积与累计频率统计关系呈现不同分布规律的现象,开展了地震峰值加速度从0.075~0.450g的6组振动台沙堆模型实验.实验重现了随振动强度增加,落沙量与累计频率从幂律分布-对数正态分布-正态分布依次转变的现象.数学分析表明,变异系数的减小,是这3种概型依次转变的原因.根据实验观察,随扰动递增沙堆表面颗粒行为呈现不同响应模式:微振动时颗粒活动性消失的概率与活动性分叉的概率在总体上平衡,当颗粒间近邻的相互作用导致连锁反应时才能发生大规模落沙事件,具有最大的不确定性.强振动时大部分颗粒就能独立启动,大规模落沙成为必然事件.据此提出,落沙规模由自组织控制的颗粒链式反应过程,向外力控制的颗粒独立下落过程的转化是导致变异系数减小的物理机制.根据以上认识,随地震烈度增加,汶川地震触发的崩塌滑坡规模与累计频率依次服从幂律分布-对数正态分布的现象,可能是具有普适性意义的规律.
According to the phenomenon of statistical relationships showing different distributions,between the area and cumulative frequency of landslides in Ⅹ,Ⅺ seismic intensity of Ms 8.0 Wenchuan earthquake,6sandpile model tests under seismic were conducted with the increase of seismic peak ground acceleration ranging from 0.075 g to 0.450 g.The phenomenon of statistical relationships was reproduced by the tests between the amount and cumulative frequency of sand changing from power-law distribution to lognormal distribution,then to normal distribution,with increase of seismic loading.By mathematical analysis,the decrease of the coefficient of variation is the cause of probability distribution shift between power-law,lognormal distribution and normal distribution.Observed through experiments,the performance of grains on the surface of sandpile will show different models with the increase of seismic loading.Under weak vibration,the probability that the activity will die is overall balanced with the probability that the activity will branch.A large-scale collapse occurs when there is a chain interaction between neighboring grains.It has the greatest uncertainty.Under strong vibration,most grains start independently.A large-scale collapse becomes a certain event.Therefore,the scale of collapse is transformed from the chain reaction of unstable grains triggered by self-organized effect to the independent falling of unstable grains triggered by vibrating force effect,which is the physical mechanism of the reducing of Cv.According to the above realization,the phenomenon of the relation between area and cumulative frequency changing from power-law distribution to lognormal distribution with the increase of seismic intensity of Ms 8.0Wenchuan earthquake may be universal.
引文
[1]BAK P,CHEN K.Self-organized criticality[J].Scientific American,United States,1991,264(1):26-33.
    [2]HELD G A,SOLINAS D H.Experimental study of criticalmass fluctuations in an evolving sand-pile[J].Physical Review Letters,1990,65(9):1120-1123.
    [3]姚令侃,黄渊,陆阳.自组织临界性及其在斜坡重力作用灾害研究中的应用[J].中国科学(E辑),2003,33(S1):17-27.YAO Lin-kan,HUANG Yuan,LU Yang.Self-organized criticality and its application in the slope disasters under gravity[J].Science in China(Series E),2003,33(S1):17-27.(In Chinese)
    [4]YAO L K,QI Y.Fractal characteristics of gravity landform and its SOC mechanism[J].Wuhan University Journal of Natural Sciences,2007,12(4):605-609.
    [5]姚令侃,李仕雄,蒋良潍.自组织临界性及其在散粒体研究中的应用[J].四川大学学报:工程科学版,2003,35(1):8-14.YAO Lin-kan,LI Shi-xiong,JIANG Liang-wei.Self-organized criticality and its application in granular mixtures[J].Journal of Sichuan University:Engineering Science Edition,2003,35(1):8-14.(In Chinese)
    [6]FUYII Y.Frequency distribution of the magnitude of landslides caused by heavy rainfall[J].Journal of the Seismological Society of Japan,1969,22(1):244-247.
    [7]HOVIUS N,STARK C P,ALLEN P A.Sediment flux from a mountain belt derived by landslide mapping[J].Geology,1997,25(3):231-234.
    [8]HOVIUS N,STARK C P,HAO-TSU C,et al.Supply and removal of sediment in a landslide-dominated mountain belt:Central Range,Taiwan[J].The Journal of Geology,2000,108(1):73-89.
    [9]YAO L K,QI Y.Fractal characteristics of gravity landform and its SOC mechanism[J].Wuhan University Journal of Natural Sciences,2007,12(4):605-609.
    [10]姚令侃,黄艺丹,杨庆华.地震触发崩塌滑坡自组织临界性研究[J].四川大学学报:工程科学版,2010,42(5):33-43.YAO Lin-kan,HUANG Yi-dan,YANG Qing-hua.The selforganized criticality of landslids triggered by earthquake[J].Journal of Sichuan University:Engineering Science Edition,2010,42(5):33-43.(In Chinese)
    [11]杨庆华,姚令侃,齐颖,等.散粒体离心模型自组织临界性及地震效应分析[J].岩土工程学报,2007,29(11):1630-1635.YANG Qing-hua,YAO Lin-kan,QI Ying,et al.Analysis of self-organized criticality of centrifugal model tests on granular mixtures and earthquake effect[J].Chinese Journal of Geotechnical Engineering,2007,29(11):1630-1635.(In Chinese)
    [12]胡海波,王林.幂律分布研究简史[J].物理,2005,34(12):889-896.HU Hai-bo,WANG Lin.A brief history of power law distributions[J].Physics,2005,34(12):889-896.(In Chinese)
    [13]LIMPERT E,STAHEL W A,ABBT M.Log-normal distributions across the sciences:keys and clues[J].BioScience,2001,51(5):341-352.
    [14]李裕奇,赵联文,王沁,等.概率论与数理统计[M].北京:国防工业出版社,2011:193-198.LI Yu-qi,ZHAO Lian-wen,WANG Qin,et al.The theory of probability and statistics[M].Beijing:National Defense Industry Press,2011:193-198.(In Chinese)
    [15]於崇文.地质系统复杂性[M].北京:地质出版社,2003,12:1019-1095.YU Chong-wen.Complexity of geosystem[M].Beijing:Geological Publishing House,2003:1019-1095.(In Chinese)
    [16]于洋.对数正态分布的几个性质及其参数估计[J].廊坊师范学院学报:自然科学版,2011,11(5):8-11.YU Yang.Several properties of the lognormal distribution and estimation of its parameters[J].Journal of Langfang Teachers College:Natural Science Edition,2011,11(5):8-11.(In Chinese)
    [17]贾俊平,何晓群,金勇进.统计学[M].北京:中国人民大学出版社,2006:102-104.JIA Jun-ping,HE Xiao-qun,JIN Yong-jin.Statistics[M].Beijing:China Renmin University Press,2006:102-104.(In Chinese)
    [18]黄艺丹,姚令侃,郭沉稳.基于元胞自动机的地震触发崩塌滑坡分布规律[J].西南交通大学学报,2013,48(4):609-615.HUANG Yi-dan,YAO Lin-kan,GUO Chen-wen.Distribution law of landslides triggered by earthquake based on cellular automata[J].Journal of Southwest Jiaotong University,2013,48(4):609-615.(In Chinese)
    [19]FRETTE V,ETAL K C.Avalanche dynamics in a pile of rice[J].Nature,1996,379(27):49-52.
    [20]BRETZ M,JEVNE B E.Imaging of avalanches in granular materials[J].Physical Review Letters,1992,69(16):2431-2434.

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