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.

土壤中颗粒的运输总是会导致机械性能的变化。这将影响土壤承受压力的能力和土方工程的可靠性。为了评估土壤的稳定性，分析土壤的织物及其过渡很重要。尽管对土壤材料运输过程的实验和分析研究的岩土技术有着悠久的传统，但基于对主要结构的分析，它的稳定性尚无标准。该研究项目的目的是确定鉴定土壤的结构在承受土壤材料的能力下的能力。根据对土壤织物的识别，得出了颗粒迁移率和土壤稳定性的一般评估。通过经验研究，3D计算机断层扫描图像以及数值模拟对土壤的织物进行可视化，分析和鉴定。在这些分析中，土壤由球体的颗粒堆积表示。这种颗粒包装将进行实验研究并进行数值模拟。为了链接这两种方法，构建了实验产生的包装的3D数据库。数字图像处理方法确定包装的相关特征值。所得包装用于验证和验证数值模拟。主要目的是鉴定织物和颗粒迁移率概率的评估。根据该评估的结果，包装暴露于特定的液压负载。该结果允许评估广泛分级粒径包装的移动颗粒的稳定性和全球迁移率。这项研究开发了鉴定颗粒包装和颗粒传输结构的方法。基于此，可以确定粒径分布和块状密度的依赖性，可以确定织物的特征类型的矩阵类型，并且可以预测迁移率的概率。结果，这项研究将有助于评估土方工程在液压负载下承受土壤材料运输的能力。这允许更准确的评估，以最大程度地减少洪水保护的土方工程中的不确定性。