Identification of poly-disperse granular fabric for the assessment of the stability of widely graded soils under hydraulic load

多分散颗粒织物的识别用于评估水力载荷下宽级配土壤的稳定性

基本信息

批准号：
318825689
负责人：
Professorin Dr.-Ing. Andrea Osburg
金额：
--
依托单位：
Lehrstuhl Bauchemie und Polymere Werkstoffe
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2017
资助国家：
德国
起止时间：
2016-12-31 至 2021-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/318825689?language=en
关键词：
Identification poly disperse granular fabric

项目摘要

The transport of particles in soil will always cause a change in the mechanical properties. This will affect the soil's capacity to withstand stresses and the reliability of earthworks. In order to assess the soil's stability, analysing the soil's fabric and its transition is important. Although there is a long tradition in geotechnics of experimental and analytic investigations into the process of the transport of the soil's material, there are no criteria for its stability based on analysis of the dominant fabric.The aim of this research project is the identification of the fabric of widely graded soils in respect of their capacity to withstand transport of soil material. On the basis of an identification of the soil's fabric, a general assessment of particle mobility and the soil's stability is derived. The soil's fabric is visualised, analysed, and identified through empirical investigation, 3D computed tomography images, and through numerical simulations. In these analyses, the soil is represented by granular packing of spheres. This granular packing will be experimentally investigated and numerically simulated. To link both methods, a 3d data base of the experimentally produced packing is built. Digital image processing methods determine the relevant characteristic values of the packing. The resulting packings are used to validate and verify the numerical simulation. The main objective is the identification of the fabric and the assessment of the probability of mobility of particles. Based on the results of this assessment the packings are exposed to a specific hydraulic load. The outcome allows an assessment of the stability and global mobility of the mobile particles of packings of widely graded particle sizes.This research develops methods of identification of the fabric of granular packings and particle transport. Based on this in dependency of the particle size distribution and bulk density a characteristic type of matrix for the fabric can be identified and the probability of mobility can be predicted. As a result, this research will contribute to techniques for assessing the capacity of earthworks to withstand transport of soil material under hydraulic loads. This allows more accurate assessments that minimize uncertainties in earthworks of flood protection.

土壤中颗粒的传输总是会引起机械性能的变化。这将影响土壤承受应力的能力和土方工程的可靠性。为了评估土壤的稳定性，分析土壤的结构及其转变非常重要。尽管在岩土工程领域对土壤材料的迁移过程进行实验和分析研究有着悠久的传统，但没有基于对主要结构的分析来确定其稳定性的标准。该研究项目的目的是识别广泛级配土壤的结构在其承受土壤材料运输的能力方面。在识别土壤结构的基础上，得出颗粒流动性和土壤稳定性的一般评估。通过实证调查、3D 计算机断层扫描图像和数值模拟，对土壤结构进行可视化、分析和识别。在这些分析中，土壤由球体的粒状堆积表示。这种颗粒堆积将进行实验研究和数值模拟。为了链接这两种方法，建立了实验生产的包装的 3D 数据库。数字图像处理方法决定了包装的相关特征值。所得填料用于验证和验证数值模拟。主要目标是识别织物并评估颗粒移动的概率。根据评估结果，填料承受特定的液压负载。结果可以评估广泛分级粒径的填料的移动颗粒的稳定性和整体流动性。这项研究开发了识别颗粒填料结构和颗粒运输的方法。基于此，根据粒度分布和堆积密度，可以识别织物基质的特征类型，并可以预测流动性的概率。因此，这项研究将有助于评估土方工程承受水力荷载下土壤材料运输能力的技术。这样可以进行更准确的评估，最大限度地减少防洪土方工程的不确定性。