PARALLEL STOCHASTIC ANALYSIS FOR GEO-ENGINEERING

地球工程并行随机分析

• 批准号: EP/D037247/1
• 负责人: Michael Hicks
• 金额: $ 12.91万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FD037247%2F1
• 关键词: PARALLEL; STOCHASTIC; ANALYSIS; GEO; ENGINEERING

[In what follows: 1. Reliability is the probability that failure will not occur; 2. A characteristic value is that single value of a material property which, when used in a deterministic analysis, will give the same response as a stochastic analysis for a given level of reliability; 3. A reduction factor is that factor (from 0.0 to 1.0) by which the mean property value is scaled to give the characteristic value.]The proposed research concentrates on the fact that natural materials are variable and that representation of this variability appears crucial to getting a realistic understanding of certain geotechnical and geo-environmental problems. A specific problem is chosen for illustrative purposes. The investigation requires one Research Associate, who will focus on: (a) converting existing finite element codes from serial to parallel environments; (b) using these optimised codes to investigate the influence of heterogeneity on 3-D slope stability. It involves a total cost of 91k plus notional service costs of 104k, and is divided into two parts:1. The stability of cut slopes in clay. This simple (total stress) application will determine reliability-based reduction factors for undrained shear strength, from which reliability-based characteristic values may be derived. Of particular interest will be the comparison between reduction factors based on 2-D and 3-D analyses: i.e. how conservative is the 2-D approach, and what economies are to be gained through basing reduction factors on the true 3-D response? The study will also investigate the influence of heterogeneity on the evolution of failure mechanisms and on the volumes of soil involved in potential slides.2. The stability of underwater sandfill slopes (using a coupled effective stress approach). The first stage will be to compare 2-D and 3-D responses for long slopes. (Hence, the remit will be similar to that for cut slopes in clay, except that the derived reduction factors will be for soil friction angle.) The second stage will consider the Nerlerk underwater berm. This structure was designed to form part of a bottom-founded oil exploration platform in the Canadian Beaufort Sea, but failed during construction (at a height of 26 m) due to static liquefaction. This complicated 3-D application will simulate the construction of the berm, and will result in predictions of the probability of failure, the height of the berm at which failure occurs, and the geometries and volumes of potential slides. (Note that there are detailed field measurements available for comparison.) Significantly, it will provide a benchmark against which previous, current and future 2-D investigations may be properly quantified.The proposed research will demonstrate a new and more meaningful approach to representing geo-structural response, with the definition of stability (reliability) now reflecting the variable nature of the material which is being analysed. Geo-environmental applications are seen as a particular area in which parallel stochastic analysis will flourish.

[以下内容：1。可靠性是不会发生故障的概率； 2。一个特征值是材料属性的单个值，当确定性分析中使用时，它将给定可靠性水平的随机分析给出相同的响应； 3。还原因子是将平均属性值缩放以产生特征值的因子（从0.0到1.0）。]拟议的研究集中在于天然材料是可变的事实，并且这种可变性的表示对于获得对某些地理技术和地理环境问题的现实理解至关重要。选择一个特定的问题是出于说明目的。调查需要一个研究助理，他们将重点关注：（a）将现有的有限元代码从串行环境转换为平行环境； （b）使用这些优化的代码研究异质性对3-D斜率稳定性的影响。它的总成本为91k加上104K的名义服务成本，分为两个部分：1。粘土中切坡的稳定性。这种简单的（总应力）应用将确定基于可靠性的剪切强度的基于可靠性的还原因子，从中可以得出基于可靠性的特征值。特别感兴趣的是基于2-D和3-D分析的还原因子之间的比较：即2-D方法的保守程度，以及通过基于真实3-D响应的还原因子来获得什么经济？该研究还将研究异质性对失效机理演变以及潜在幻灯片中涉及的土壤的体积的影响。2。水下沙填充坡度的稳定性（使用耦合的有效应力方法）。第一阶段将是比较长斜率的2-D和3-D响应。 （因此，在粘土中的斜坡将与斜坡切成薄片相似，但衍生的还原因子将用于土壤摩擦角。）第二阶段将考虑Nerlerk水下护堤。该结构旨在构成加拿大Beaufort Sea中底部基础勘探平台的一部分，但由于静态液化，在建筑过程中（高度为26 m）失败了。这种复杂的3-D应用将模拟BER的构建，并将预测故障的概率，发生故障发生的BER的高度以及潜在幻灯片的几何形状和体积。 （请注意，可以进行比较的详细现场测量。）它将提供一个基准，可以对其进行适当量化以前的，当前和将来的2D研究。拟议的研究将证明一种新的，更有意义的方法来代表地理结构响应，以代表稳定性（可靠性（可靠性））现在反映了材料可变性质的定义。地理环境应用被视为特定领域，在该领域中，平行随机分析将蓬勃发展。