颗粒柱体崩塌涌浪产生机制研究  

Research on the mechanism of impulse wave generated by the collapse of granular column

作　　者：黄波林[1] 王健[1] HUANG Bolin;WANG Jian(Hubei Key Laboratory of Disaster Prevention and Mitigation,China Three Gorges University,Yichang,Hubei 443002,China)

机构地区：[1]三峡大学防灾减灾湖北省重点实验室,湖北宜昌443002

出　　处：《岩石力学与工程学报》2020年第S02期3496-3504,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家重点研发计划项目(2018YFC1504806,2018YFC1504803)。

摘　　要：岸边悬崖带通常发育有柱状危岩体,它的压溃崩塌解体入水会产生灾难性的涌浪。开展PIV技术支持下颗粒柱体崩塌涌浪物理试验11组,首次展现崩塌颗粒体–水体耦合运动矢量过程,采用现象分析、理论公式验证和回归推导等方法对数据及影像进行研究。试验表明,底部颗粒体的推移是造成水体向上向外形成涌浪运动的主要作用方式;柱体越高,产生的最大涌浪波幅越大,柱体势能的最终损失率越大;最大涌浪产生于崩塌停止之前,崩塌体最终势能损失率为37%~75%;颗粒柱体崩塌产生的涌浪波类型包括推进波和过渡波两种,其中的类孤立波波形与KdV理论解的平均偏差误差仅5.4%;最大涌浪波波幅存在"饱和"现象,其临界形状系数a=5,即a≥5后产生的最大涌浪波幅基本保存不变;据此,非线性回归推导并讨论了最大波幅的阶段性预测函数,函数预测值与试验值差值百分比为0.03%~6.7%;它更适合于预测柱体压溃崩塌产生的涌浪。该研究可为水库区或海岸线柱状危岩体崩塌产生的涌浪预测提供技术支撑。There are usually columnar dangerous rock masses in the cliff coastline near the bank,which will generate catastrophic impulse wave when it fails with disintegration and plunges into the water.In this study,11 groups of physical experiments were carried out on the basis of PIV technology.For the first time,the coupled motion vector process of avalanche particles and water body was shown.The data and pictures of the tests were analyzed by the methods of phenomenon analysis,theoretical formula verification and data regression.The test results showed that the pushment of particles at the bottom was the main way to cause the water body to form wave upward and outward.The higher the column was,the bigger maximum impulse wave was.The time of the generation of maximum impulse wave was earlier than the time of the stop of the collapse.The final potential energy loss rate of granular column was about 37%–75%.There were two types of waves generated by the collapse of the granular column,i.e.the translation wave and the transition wave,among which the solitary wave form was in good agreement with KdV’s theoretical solution:the average deviation error was only 5.4%.There existed a"saturation"phenomenon for the maximum amplitude of impulse wave.The critical shape coefficient a was 5,that is to say,the amplitude of wave generated was basically kept unchanged when a≥5.Therefore,the step prediction functions of the maximum amplitude were discussed by nonlinear regression,the percentage of difference between predicted value and experimental value was about 0.03%–6.7%.These functions are more suitable for the prediction of the impulse wave generated by the buckling collapse of the granular column.This study can provide technical support for the hazard prevention and mitigation of columnar dangerous rock mass in reservoir area or coastline.

关 键 词：岩石力学 柱状危岩体 PIV技术 能量传递 饱和机制 涌浪预测 

分 类 号：TU45[建筑科学—岩土工程]