在不同的负载率和温度和湿度周期下,绝缘混凝土的可变角度-剪切测试和分析
Gejun Tong1,2, Jingzhao Shen1, Jianyong Pang2
1State Key Laboratory for Safe Mining of Deep Coal and Environment Protection, Huainan Mining (Group) Co., Ltd, Huainan 232000, China.
PloS one
|April 18, 2024
概括
这项研究研究了在深层矿山中热绝缘喷混凝土的剪切强度. 调查结果表明,加载率和温度周期显著影响喷混凝土的强度,这对于安全的地下操作至关重要.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
背景情况:
- 深层矿山面临着热损伤的挑战.
- 热绝热是道路绝缘和安全生产的重要组成部分.
- 了解 shotcrete 在炎热,潮湿和压力环境中的剪切强度是必要的.
研究的目的:
- 为了评估新型热绝缘喷混凝土的剪切强度.
- 分析加载速率和温度/湿度周期对喷混凝土性能的影响.
- 开发经验式方程,用于预测 shotcrete 的行为.
主要方法:
- 在射击混凝土样本上进行了可变角度剪切测试.
- 测试是在不同的加载速度下进行的.
- 额外的测试包括温度和湿度周期.
主要成果:
- 峰值剪切应力最初增加,然后随着加载速度而下降.
- 增加倾斜角放大了负载率的影响.
- 在周期性条件下,切削强度显示出随温度增加,然后随温度下降的趋势.
结论:
- 负载率和环境周期显著影响保温 shotcrete 的剪切强度.
- 使用MATLAB开发了经验方程,以建模凝聚力和内部摩擦角度.
- 结果为在深井项目中管理地热温度提供了技术指导.
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