权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Automating particle size and shape measurement in soil mechanics

土壤力学中颗粒尺寸和形状的自动化测量

基本信息

批准号：
EP/F068778/1
负责人：
Catherine O'Sullivan
金额：
$ 8.87万
依托单位：
Imperial College London
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2008
资助国家：
英国
起止时间：
2008 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FF068778%2F1
关键词：
Automating particle size shape measurement

项目摘要

It is well established that the geometry (size and shape) of the individual particles influences the overall response of a granular material to applied loads and deformations. Traditionally in soil mechanics we measured the size of soil particles by passing the particles through a succession of sieves with different aperture sizes. Shape was measured qualitatively, by comparing the shape of a small number of particles with standard (2D) charts. These methods have some disadvantages. Considering sieving, we have no information about the distribution of particle sizes between the standard sieve intervals. The results of a sieve analysis are not always consistent, especially when long platy particles are involved. Changes in particle size distribution are used to assess damage to the individual particles, and the small changes we need to measure cannot be reliably detected using a sieve analysis. Regarding shape analysis, we know that particles in granular materials are three-dimensional. We also know that to get a statistically valid assessment of particle shape and particle shape variation in a granular material, the shape of thousands of particles should be considered. The traditional simple, visual description of particle geometry does not allow objective, quantitative, three-dimensional shape analysis of statistically meaningful numbers of particles. A new technology, the QicPic apparatus manufactured by Sympatec, includes a system for dispersing particles, a high speed camera and sophisticated image analysis software to measure particles sizes and shapes. This apparatus overcomes the limitations of the traditional low tech approaches, allowing 3D assessment of size and shape for large numbers of particles. We have had access to this apparatus, it was installed in our laboratory for a one-week trial period. During this period we established that the apparatus can produce valid measurements for the particles we are interested in, it can easily be used by our research students, and the degree of sophistication of the output (including black and white images of individual particles) makes it a good tool for fundamental research on particle morphology.This apparatus would provide us with improved capabilities for quality control for a range of experimental work involving granular materials in the department. These materials include natural and artificial sands used in soil mechanics research, morsellised bone used in biomedical engineering research and artificial aggregates that are being developed from waste by-products as environmental engineering research. The apparatus can also be used to better understand how the individual particles are damaged when a granular material is loaded and deformed, and this understanding is important for developing numerical models of the material. The apparatus would also be useful to support ongoing research that will develop a relationship between the overall material response and the characteristics of the constituent particles.The applicants are already collaborating to develop methods to quantify both particle strength and particle geometry and relate these characteristics to the overall material response. Our current facilities include an optical microscope,a surface mapping microscope, and single particle mechanical apparatii. This apparatus would complement these tools, and strengthen our expertise in this area.

已经确定的是，单个颗粒的几何形状（尺寸和形状）影响颗粒材料对施加的载荷和变形的总体响应。传统上，在土壤力学中，我们通过使颗粒通过一系列具有不同孔径尺寸的筛子来测量土壤颗粒的尺寸。通过将少量颗粒的形状与标准（2D）图表进行比较，定性测量形状。这些方法有一些缺点。考虑到筛分，我们没有关于标准筛分间隔之间粒度分布的信息。筛分分析的结果并不总是一致的，特别是当涉及长片状颗粒时。粒度分布的变化用于评估单个颗粒的损伤，而我们需要测量的微小变化无法使用筛分分析可靠地检测到。关于形状分析，我们知道颗粒材料中的颗粒是三维的。我们还知道，为了对颗粒材料中的颗粒形状和颗粒形状变化进行统计有效的评估，应该考虑数千个颗粒的形状。传统的颗粒几何形状的简单、直观描述不允许对统计上有意义的颗粒数量进行客观、定量、三维形状分析。新帕泰克公司生产的QicPic设备是一项新技术，包括一个分散颗粒的系统、一个高速摄像机和先进的图像分析软件，用于测量颗粒的大小和形状。该设备克服了传统低技术方法的局限性，允许对大量颗粒的尺寸和形状进行3D评估。我们已经使用了这台仪器，它被安装在我们的实验室进行了一周的试用。在此期间，我们确定该设备可以对我们感兴趣的粒子进行有效的测量，它可以很容易地被我们的研究学生使用，以及输出的复杂程度（包括单个颗粒的黑色和白色图像）使其成为颗粒形态学基础研究的良好工具。该装置将为我们提供一系列实验的质量控制能力本部门涉及粒状材料的工作。这些材料包括用于土壤力学研究的天然和人造砂、用于生物医学工程研究的碎骨以及作为环境工程研究而从废弃副产品中开发的人造骨料。该设备还可以用来更好地了解如何单个颗粒被损坏时，粒状材料加载和变形，这种理解是重要的，为开发材料的数值模型。该装置还将有助于支持正在进行的研究，该研究将开发整体材料响应与组成颗粒的特性之间的关系。申请人已经在合作开发量化颗粒强度和颗粒几何形状的方法，并将这些特性与整体材料响应相关联。我们目前的设备包括光学显微镜、表面测绘显微镜和单粒子机械装置。这一机制将补充这些工具，并加强我们在这一领域的专门知识。