岩质斜坡地震稳定性的快速评价是学者们关注的热点和难点。传统上,大多数研究采用图表法得到的安全系数快速评价岩质斜坡的地震稳定性,目前缺乏快速计算岩质斜坡临界加速度的方法。如何构建临界加速度模型是计算斜坡永久位移的前提条件。为此,采用有限元极限分析方法(平均界解)和广义Hoek-Brown强度准则,提出了一种快速计算岩质斜坡临界加速度的新方法。对概化岩质斜坡进行数值建模,基于1 960次的案例计算结果,绘制了岩质斜坡临界加速度图,通过2次拟合统计分析,构建了岩质斜坡临界加速度与斜坡几何条件和强度参数的函数表达式,并将本文方法与Newmark模型和数值解进行了比较。结果表明,本文方法的计算精度比Newmark模型更接近数值解。所开发的岩质斜坡永久位移计算方法高效、便捷,不仅能够用于单体斜坡地震稳定性的快速计算,还可以为计算区域尺度内大量斜坡的永久位移提供技术支撑。
Abstract
The rapid calculation of seismic stability of rock slopes remains a prominent and challenging focus among scholars. Historically, the chart method has been predominant in acquiring safety factors to swiftly evaluate the seismic stability of such slopes. However, approaches for promptly determining the critical acceleration of rock slopes are in lack. Establishing a model for critical acceleration is a prerequisite for computing the permanent displacement of slopes. To address this issue, we present a novel approach for swiftly computing the critical acceleration of rock slopes by employing the finite element limit analysis method (mean bound solution) and the generalized Hoek-Brown strength criterion. We obtained the diagram of critical acceleration based on 1 960 case calculations via numerical simulations for a generalized rock slope. Subsequent to two fitting statistical analyses, we derived a functional relationship between the critical acceleration of rock slopes and their geometric attributes and strength parameters. Comparisons of the results of the proposed method with those of the Newmark model and numerical solutions demonstrate that the computational accuracy of the proposed method aligns more closely with numerical solutions compared to the Newmark model. The developed method for calculating permanent displacement in rock slopes proves efficient and convenient. It not only facilitates the rapid assessment of seismic stability for individual slopes but also offers technical support for calculating permanent displacement across a large number of slopes on regional scale.
关键词
岩质斜坡 /
图表法 /
有限元极限分析 /
广义Hoek-Brown强度准则 /
临界加速度 /
Newmark模型 /
永久位移 /
快速计算
Key words
rock slope /
stability charts /
finite element limit analysis /
generalized Hoek-Brown strength criterion /
critical acceleration /
Newmark model /
permanent displacement /
rapid calculation
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] TAYLOR D W. Stability of Earth Slopes[J]. Journal of the Boston Society of Civil Engineers, 1937, 24(3) :197-246.
[2] GENS A, HUTCHINSON J N, CAVOUNIDIS S. Three-dimensional Analysis of Slides in Cohesive Soils[J]. Géotechnique, 1988, 38(1): 1-23.
[3] BAKER R. A Second Look at Taylor’s Stability Chart[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2003, 129(12): 1102-1108.
[4] STEWARD T, SIVAKUGAN N, SHUKLA S K, et al. Taylor’s Slope Stability Charts Revisited[J]. International Journal of Geomechanics, 2011, 11(4): 348-352.
[5] MICHALOWSKI R L.Stability Charts for Uniform Slopes[J].Journal of Geotechnical and Geoenvironmental Engineering,2002,128(4):351-355.
[6] TANG G P, ZHAO L H, LI L, et al. Stability Charts of Slopes under Typical Conditions Developed by Upper Bound Limit Analysis[J]. Computers and Geotechnics, 2015, 65: 233-240.
[7] JIANG X Y, CUI P, LIU C Z. A Chart-based Seismic Stability Analysis Method for Rock Slopes Using Hoek-brown Failure Criterion[J]. Engineering Geology, 2016, 209: 196-208.
[8] LI A J,MERIFIELD R S,LYAMIN A V.Stability Charts for Rock Slopes Based on the Hoek-Brown Failure Criterion[J].International Journal of Rock Mechanics and Mining Sciences,2008,45(5):689-700.
[9] LI A J,LYAMIN A V,MERIFIELD R S.Seismic Rock Slope Stability Charts Based on Limit Analysis Methods[J].Computers and Geotechnics,2009,36(1/2):135-148.
[10] LI A J, MERIFIELD R S, LYAMIN A V. Effect of Rock Mass Disturbance on the Stability of Rock Slopes Using the Hoek-Brown Failure Criterion[J]. Computers and Geotechnics, 2011, 38(4): 546-558.
[11] TAHERI A,TANI K. Assessment of the Stability of Rock Slopes by the Slope Stability Rating Classification System[J]. Rock Mechanics and Rock Engineering,2010,43(3):321-333.
[12] SUN C, CHAI J, LUO T, et al. Stability Charts for Pseudostatic Stability Analysis of Rock Slopes Using the Nonlinear Hoek-Brown Strength Reduction Technique[J]. Advances in Civil Engineering, 2020, 2020: 8841090.
[13] HOEK E, BROWN E T. Empirical Strength Criterion for Rock Masses[J]. Journal of the Geotechnical Engineering Division, 1980, 106(9): 1013-1035.
[14] HOEK E.Hoek-Brown Failure Criterion-2002 Edition[C] //Proceedings of NARMS-TAC 2002.Toronto, Canada. July 7-10,2002: 267-273.
[15] KRABBENHOFT K, LYAMIN A V. Strength Reduction Finite-element Limit Analysis[J]. Géotechnique Letters, 2015, 5(4): 250-253.
[16] JIBSON R W, HARP E L, MICHAEL J A. A Method for Producing Digital Probabilistic Seismic Landslide Hazard Maps[J]. Engineering Geology, 2000, 58(3/4): 271-289.
[17] NEWMARK N M. Effects of Earthquakes on Dams and Embankments[J]. Géotechnique, 1965, 15(2): 139-160.
[18] JIBSON R W. Regression Models for Estimating Coseismic Landslide Displacement[J]. Engineering Geology, 2007, 91(2/3/4): 209-218.
[19] AMBRASEYS N N, MENU J M. Earthquake-induced Ground Displacements[J]. Earthquake Engineering & Structural Dynamics, 1988, 16(7): 985-1006.
基金
贵州省教育厅高等学校科学研究项目(青年项目)(黔教技[2022]361);国家自然科学基金项目(42307269,42107195);凯里学院博士启动专项课题(BS20230101);黔东南州科技计划项目(黔东南科合J字([2022]51号));安阳市重点研发与推广科技攻关项目(2023C01SF211)