中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
管沟开挖土质边坡稳定性控制

文献类型:学位论文

作者谢江
学位类别硕士
答辩日期2014
授予单位中国科学院研究生院
授予地点北京
导师李泳 ; 赵宇
关键词管沟开挖 标度分布 颗分参数 土体强度 参数 边坡稳定性
其他题名Stability controlling of soil slope under excavating of oil and gas pipeline
学位专业岩土工程
中文摘要输油气管道沿坡脚敷设,需要穿越各种类型土体的边坡,如黄土、碎石土、崩塌堆积体等。在管沟开挖过程中,土质边坡常常因扰动而失稳,给工程带来重大损失。本文通过数值模拟方法研究管沟开挖边坡的变形过程,其特色在于,基于土体颗粒的普适性分布,对土体进行分类,并建立颗分参数与土力学性质、特别是土体强度参数的关系,并由此模拟不同土体、不同坡型的破坏过程。主要结论如下: 1)通过大量土体样本,确立颗粒分布P (D) = RD – μexp (– D/Dc),运用颗分参数(μ, Dc)对不同类型土体进行分类(表2-3)。 2)通过系列实验和文献数据,建立了颗分参数(μ, Dc)与土体强度参数(c, φ)的关系:c= 25.61exp(-48.16μ)+ 4.385,φ=0.5038Dc+15.48。由此提出一定条件下(含水率15%、密度1.8g/cm3等)不同土体强度参数的取值范围(表3-9)。 3)运用FLAC-3D软件,以(μ, Dc)-(c, φ)关系为边界条件,模拟不同土体类型和几何形态的边坡在管道开挖作用下的变形和失稳过程,确立了一定条件下的极限坡度(表4-7、4-8)。管道沿坡脚敷设过程中主要穿越坡积土、坡体残积碎石土、风化根植土几类,在条件一致的情况下,坡体残积土最稳定,根植土次之,坡积土最不稳定。 4)比较了坡形对边坡稳定性的影响。当坡体直径与坡体高度之比λ大于等于1时,凸形坡比凹形坡更趋于稳定,在管沟开挖作用下,变形更小,当λ小于时,凹形坡比凸形坡更趋于稳定。 5)基于数值模拟结果,提出边坡开挖工程控制的建议。
英文摘要Oil and gas pipeline generally pass through slopes of various soils, such as Loess, gravelly soil and talus soil; and slope excavation often causes slope failure threatening the pipeline engineering. In this paper, We research the influence of pipeline excavating by using numerical simulation method. We classify soils and we study the relationships between parameters (μ, Dc) and (c, φ) and other parameters such as permeability coefficient basing on the distribution, P (D) = RD – μexp (– D/ Dc), which is satis?ed well by various soils. The main contents are as follows: (1) soil grain fit well with the distribution: P (D) = RD – μexp (– D/Dc). Soils are classified by (μ, Dc) (Table 2-3) (2) Distribution parameters (μ, Dc) have a relation with (c, φ) like this: c= 25.61exp(-48.16μ)+ 4.385,φ=0.5038 Dc +15.48. By using this kind of relationship, we proposed the scope of strength parameters (table 3-9) of different soil under specific condition (moisture content 15%、density 1.8g/cm3). (3) We get the limit values of the slope gradient when the failure happened under the effecting of excavating of pipeline based on the relations between (μ, Dc) and (c, φ) by using soft FLAC-3D. The statistical results are in table 4-7 and 4-8. According to the site investigation, we find that colluvial soil, residual soil and vegetation soil are the common soils that pipeline passing through. The residual soil is the most favorable soil to slope stability, and vegetation soil is the middle one while colluvial soil is the last one. (4) We research the influence of slope shapes to the stability of soil slope. We find that convex slope are more stable than concave slope when λ is no less than 1, where λ is the ratio of slope height and the diameter. On the contrary, when λ is less than 1, concave slope are more stable than convex slope. (5) We propose some measures to control the stability of slopes basing on the result of numerical simulation
语种中文
源URL[http://ir.imde.ac.cn/handle/131551/8029]  
专题成都山地灾害与环境研究所_山地灾害与地表过程重点实验室
推荐引用方式
GB/T 7714
谢江. 管沟开挖土质边坡稳定性控制[D]. 北京. 中国科学院研究生院. 2014.

入库方式: OAI收割

来源:成都山地灾害与环境研究所

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