用颗粒来确定煤炭的Mode-I静态断裂度的新方法
Qiang Cheng1,2, Gun Huang1,2, Jie Zheng3
1State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400030, China.
Materials (Basel, Switzerland)
|April 27, 2024
概括
这项研究建立了一种方法,使用硬度系数和压碎特性快速确定煤炭断裂性. 这有助于通过了解煤炭来有效地采矿和预防灾害.
科学领域:
- 地质力学 地质力学
- 材料科学 材料科学 材料科学
- 采矿工程 采矿工程 采矿工程
背景情况:
- 煤炭的机械性能对于采矿的安全性和效率至关重要.
- 煤炭中的裂和裂复杂化了用于断裂性测试的标准样品准备.
- 易于测量的工程指标,如硬度系数 (f值) 和Hardgrove磨砂度指数 (HGI) 存在.
研究的目的:
- 开发一种快速而准确的方法来确定煤炭的Mode-I断裂性.
- 为了建立煤炭特性 (硬度,可研磨性) 和断裂性之间的关系.
- 为了研究粒子大小和破裂能量对新表面积分布的影响.
主要方法:
- 使用不同颗粒大小 (1-2毫米,0.425-1毫米) 的划分半圆曲线 (NSCB) 样本进行的实验.
- 进行了下降重量,研磨,单轴压力强度和三点曲试验.
- 开发了理论模型,涉及硬度系数,压碎工作比率,等效直径和断裂性.
主要成果:
- 煤炭硬度系数与压碎工作比率成正比,与平均相当直径成反比例.
- 断裂性平方是与压碎工作比率和平均等效直径成正比的,与新增加的面积和硬度系数成反比例的.
- 模式I断裂性可以快速确定使用密度,压碎等值直径和弹性模量.
结论:
- 一种新的方法可以快速准确地确定煤炭断裂性.
- 这些发现将易于测量的煤炭特性与关键的断裂性参数联系起来.
- 了解粒子破裂和表面积分布是预测机械行为的关键.
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