Calculation on wave-induced seabed sliding instability and the sliding failure characteristics
-
摘要: 波浪引起的海床不稳定性是海洋工程中需要考虑的重要问题。在对现有波致海床滑动稳定性计算方法进行分析的基础上,提出了一种波致海床滑动稳定性计算的全应力状态法,将其与现有计算方法进行了对比分析,并进一步研究了波致砂土海床和软土海床的滑动失稳特征。结果分析表明,全应力状态法在波致海床滑动稳定性分析中具有较好的适用性。对于砂土海床,其滑动稳定性受饱和度的影响较大,且当海床计算厚度约为0.2倍波长时对应的滑动深度最大。波浪作用下坡度不超过2°的均质软土海床,其最危险滑动面的位置仅与波长有关,其滑动深度约为0.21倍波长,滑动面半弦长约为0.33倍波长;海床表面的波压力数值只影响其安全系数的大小,而不影响其滑动深度。Abstract: Wave-induced seabed instability is an important problem considered by ocean engineers. On basis of analyzing the present calculation methods for wave-induced seabed sliding instability, a new method, referred to the overall stress state method, is established to calculate the seabed sliding stability under wave loading. The new method has been compared with others, and the wave-induced sliding failure characteristics of sandy seabed and the soft clay one has been analyzed. The results have shown that the overall stress state method is applicable to compute the seabed sliding instability. For sandy seabed, saturation has great influence on its sliding instability, and the sliding depth will reach the maximum when the seabed thickness is 0.2 times of the wave length. For homogeneous soft clay seabed with slope angle no larger than 2°under wave loading, location of the most dangerous sliding surface is only related with the wave length, that is, the sliding depth is 0.21 times of the wave length and the half chord length of sliding arc is 0.33 times of the wave length. The wave pressure has influences only on factor of safety of the most dangerous sliding surface of the soft clay seabed, not on the sliding depth.
-
Key words:
- wave /
- seabed /
- sliding instability /
- stress state
-
Henkel D J. The role of waves in causing submarine landslides[J]. Géotechnique, 1970, 20(1):75-80. Okusa S, Yoshimura M. Wave-induced instability in sandy submarine sediments[J]. Soils & Foundations, 1987, 27(4): 62-72. 孙永福,董立峰,蒲高军, 等. 风暴潮作用下黄河水下三角洲斜坡稳定性研究[J]. 工程地质学报, 2006, 14(5): 582-587. Sun Yongfu, Dong Lifeng, Pu Gaojun, et al. Stability analysis of slopes in the subaqueous delta of the yellow river under storm wave loading[J]. Journal of Engineering Geology, 2006, 14(5): 582-587. 常方强, 贾永刚. 黄河口水下斜坡波致圆弧振荡剪切破坏分析[J]. 海洋学报, 2010, 32(5):175-179. Chang Fangqiang, Jia Yonggang. The analysis on the arc oscillatory shear failure induced by wave on the seabed in the Huanghe Estuary[J]. Haiyang Xuebao, 2010, 32(5):175-179. 许国辉. 波浪导致粉质土缓坡海底滑动的研究——以黄河水下三角洲为例[D]. 青岛: 中国海洋大学, 2006. Xu Guohui. Study on the landslide of gentle-slope silty seabed under waves—A case of Yellow River subaqueous delta[D]. Qingdao: Ocean University of China, 2006. Rahman M S. Wave-induced instability of seabed: Mechanism and conditions[J]. Marine Geotechnology, 1991, 10: 277-299. 张亮, 栾锡武. 南海北部陆坡稳定性定量分析[J]. 地球物理学进展, 2012, 27(4): 1443-1453. Zhang Liang, Luan Xiwu. Quantitative analysis of submarine slope stability on the northern slope of the South China Sea[J]. Progress in Geophysics, 2012, 27(4): 1443-1453. 叶银灿, 陈锡土, 宋连清, 等. 浙江北部岛屿海域土体稳定性研究[J]. 东海海洋, 1996, 14(1): 1-18. Ye Yincan, Chen Xitu, Song Lianqing, et al. A study for the seafloor sediment stability around the island areas of northern Zhejiang Province[J]. Donghai Marine Science, 1996, 14(1): 1-18. 刘小丽, 窦锦钟, 英姿,等. 波致海底缓倾角无限坡滑动稳定性计算分析探讨[J]. 海洋学报, 2015, 37(3):99-105. Liu Xiaoli, Dou Jinzhong, Ying Zi, et al. Wave-induced stability analysis on submarine infinite slopes with gentle dip angle[J]. Haiyang Xuebao, 2015, 37(3):99-105. 张恒, 来向华, 廖林燕, 等. 基于强度折减法的海底边坡三维稳定性分析[J]. 水运工程, 2016(4): 148-153. Zhang Heng, Lai Xianghua, Liao Linyan, et al. Analysis of 3-D modeling subsea-slope stability based on strength reduction methods[J]. Port & Waterway Engineering, 2016(4): 148-153. 杨林青, 王忠涛, 李家钢, 等. 基于强度折减理论的海底斜坡稳定性分析[J]. 水利与建筑工程学报, 2012, 10(6):26-30. Yang Linqing, Wang Zhongtao, Li Jiagang, et al. Submarine slope stability analysis based on strength reduction theory[J]. Journal of Water Resources and Architectural Engineering, 2012, 10(6):26-30. 刘敏, 刘博, 年廷凯, 等. 线性波浪加载下海底斜坡失稳机制的数值分析[J]. 地震工程学报, 2015, 37(2): 415-421. Liu Min, Liu Bo, Nian Tingkai, et al. Numerical analysis of the failure mechanism of submarine slopes under linear wave loading[J]. China Earthquake Engineering Journal, 2015, 37(2): 415-421. Nian Tingkai, Liu Bo, Yin Ping. Seafloor slope stability under adverse conditions using energy approach[J]. Applied Mechanics & Materials, 2013, 405-408: 1445-1448. 刘博, 年廷凯, 刘敏, 等. 基于极限分析上限方法的海底斜坡稳定性评价[J]. 海洋学报, 2016, 38(7): 135-143. Liu Bo. Nian Tingkai, Liu Min, et al. Stability of seafloor slopes based on upper bound approach of limit analysis[J]. Haiyang Xuebao, 2016, 38(7): 135-143. Rahman M S, Jaber W Y. Submarine landslides: Elements of analysis[J]. Marine Geotechnology, 1991, 10: 97-124. Hsu J R C, Jeng D S. Wave-induced soil response in an unsaturated anisotropic seabed of finite thickness[J]. International Journal for Numerical & Analytical Methods in Geomechanics, 1994, 18(11): 785-807. 叶银灿. 中国海洋灾害地质学[M]. 北京:海洋出版社,2012. Ye Yincan. Marine Hazard Geology[M]. Beijing: China Ocean Press, 2012.
点击查看大图
计量
- 文章访问数: 824
- HTML全文浏览量: 8
- PDF下载量: 628
- 被引次数: 0