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张智敏

（中铁一院集团 陕西铁道工程勘察有限公司，陕西 西安 710043）

摘 要：以煤岩为研究对象，进行不同浸润时间下的单轴压缩蠕变试验。试验表明，煤岩在轴向应力加载瞬间，产生瞬时弹性应变，接着出现衰减、稳定蠕变，当加载应力高于长期强度时，表现出加速蠕变行为；通过等时应力-应变曲线求拐点的方式，确定煤岩长期强度，随着浸润时间的增长而递减。基于煤岩蠕变的黏弹塑性，确定基础蠕变模型，利用考虑损伤的Hooke体描述煤岩瞬时弹性应变，分数阶黏滞体表征黏弹性应变，分数阶黏塑性体反映黏塑性应变，构建一个新的改进后的煤岩蠕变力学模型。结果表明，改进后模型对煤岩蠕 变曲线具有良好模拟效果，能较为准确反映煤岩在不同浸润时间下的蠕变力学行为。

关键词：浸润时间；煤岩；加速蠕变；长期强度；模型

中图分类号：TD315            

文献标志码：A     

文章编号：1005-8249（2024）02-0039-06

DOI：10.19860/j.cnki.issn1005-8249.2024.02.008

 

ZHANG Zhimin

(China Railway First Institute Group Shaanxi Railway Engineering Survey Co., Ltd.,  Xi'an 710043，China)

Abstract: Conduct uniaxial compression creep tests on coal and rock under different infiltration times. The experiment shows that coal rock undergoes instantaneous elastic strain at the moment of axial stress loading, followed by attenuation and stable creep. When the loading stress is higher than the long-term strength, it exhibits accelerated creep behavior; By calculating the inflection point through the isochronous stress-strain curve, the long-term strength of coal and rock is determined, which decreases with the increase of infiltration time. Based on the viscoelastic plasticity of coal rock creep, a basic creep model is determined. The Hooke volume considering damage is used to describe the instantaneous elastic strain of coal rock, the fractional order viscous body represents the viscoelastic strain, and the fractional order viscous plastic body reflects the viscoelastic strain. A new improved mechanical model of coal rock creep is constructed. The results indicate that the improved model has a good simulation effect on the creep curve of coal and rock, and can accurately reflect the creep mechanical behavior of coal and rock under different infiltration times.

Keywords: infiltration time; coal rock; accelerated creep; long-term strength; model

*基金项目：中国地质调查局二级项目（DD20201119）。

作者简介：张智敏（1987—），男，满族，本科，工程师，主要研究方向：地质勘察工作。

收稿日期：2023-08-17