马斌,刘永玺,李会平,等. 窄深河谷近坝库岸滑坡涌浪特性及传播规律[J]. 水利水运工程学报,2021(5):120-128. doi: 10.12170/20210416001
引用本文: 马斌,刘永玺,李会平,等. 窄深河谷近坝库岸滑坡涌浪特性及传播规律[J]. 水利水运工程学报,2021(5):120-128. doi: 10.12170/20210416001
(MA Bin, LIU Yongxi, LI Huiping, et al. Surge characteristics and propagation of landslide near the dam in narrow river valley[J]. Hydro-Science and Engineering, 2021(5): 120-128. (in Chinese)). doi: 10.12170/20210416001
Citation: (MA Bin, LIU Yongxi, LI Huiping, et al. Surge characteristics and propagation of landslide near the dam in narrow river valley[J]. Hydro-Science and Engineering, 2021(5): 120-128. (in Chinese)). doi: 10.12170/20210416001

窄深河谷近坝库岸滑坡涌浪特性及传播规律

Surge characteristics and propagation of landslide near the dam in narrow river valley

  • 摘要: 大比尺水工模型试验可获得更接近原型的相似现象,对窄深河谷近坝库区可能发生的整体大体积滑坡工况进行试验研究,结合三维数值模型分析滑坡次生涌浪的产生、传播和消散特性。研究结果表明:数值模型计算的浪高、相位与试验结果基本一致,库区涌浪类型属于有限水深波,波能沿水深方向均有分布;涌浪产生区附近非线性较强,受窄深地形影响,波高在传播过程中快速衰减,坝肩处涌浪叠加出现瞬时越浪;试验中涌浪近场波形只观测到弱非线性振荡波;试验范围内块体模型冲击动能转化率为2%~19%,滑块动能转化率与相对体积、相对厚度呈正相关,与滑块入水弗劳德数呈负相关;低频波受地形影响较大,在岸坡浅水区域出现波能的暂时集中,谱峰值增大,随时间推移库区水域高频波增多。对于窄深河谷中的大体积滑坡次生涌浪,尽管首浪波能受高陡边坡影响,传播至坝前时波高已明显削减,但坝前最大浪高往往由涌浪反射叠加形成,在首浪到达之后仍存在翻坝风险。

     

    Abstract: Large-scale hydraulic model tests can obtain similar phenomena closer to the prototype. We conducted experimental research on the overall large-scale landslide conditions that might occur in the near-dam reservoir area, and analyzed the generation, propagation and dissipation characteristics of surge caused by landslides in combination with a three-dimensional numerical model. The results show that the wave height and phase calculated by the numerical model are basically consistent with the experimental results. The type of surge in the reservoir area is a finite depth wave, and the wave energy is distributed along the depth of the water. The nonlinearity near the surge generation area is strong, and the wave height decays rapidly as it propagates; the superposition of surge at the dam abutment appears instantaneous surging. In the test, only weakly nonlinear oscillatory waves were observed in the near field waveform of surge waves. Under the experimental conditions, the impact kinetic energy conversion rate of the block model is about 2%~19%. The kinetic energy conversion rate of the slider is positively correlated with the relative volume and relative thickness, and negatively correlated with the Froude number. The low frequency wave is greatly affected by the topography, and the wave energy temporarily concentrates in the shallow water area of the bank slope, the spectral peak increases, and the high frequency wave composition increases with time passing. For narrow and deep valleys, surges are caused by large amount of landslides. Although the wave energy of the first wave is affected by the high and steep slope, the wave height in front of the dam is obviously reduced, but the maximum wave height in front of the dam is usually formed by reflection and superposition of surges. After the first wave arrives, there is still a risk of surges over the dam body.

     

/

返回文章
返回