温度应力测试机器的开发和初步应用,用于现场造内部轴层
Chi Zhang1, Shuaishuai Wang1, Tao Zhang2
1State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou 221116, China.
Materials (Basel, Switzerland)
|June 28, 2023
概括
破解冷的轴心内部墙壁是一个越来越大的问题. 这项研究开发了一种新的测试机器来分析混凝土的应力和裂纹,为预防策略提供了洞察力.
科学领域:
- 土木工程 土木工程是指土木工程.
- 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:
- 中国的轴线深度和直径的增加加剧了冷的轴内部墙壁的裂和水泄漏.
- 这造成了严重的安全威胁和经济损失,需要了解造内部墙壁的应力变化.
- 当前的温度应力测试机器在样品形状,温度控制和轴承能力方面存在局限性.
研究的目的:
- 开发一款专门为内墙结构设计的新型温度应力测试机.
- 在施工过程中模拟水化热和约束效应在现场造的内墙上.
- 在模拟的施工条件下研究内部墙壁的温度,应变和应力变化.
主要方法:
- 开发一种可适应内壁形状的新型温度应力测试机器,并模拟水化热.
- 根据相似性标准制造一个缩小规模的内墙模型.
- 在100%的终极约束条件下模拟水化加热和冷却过程,以监测温度,应变和应力.
主要成果:
- 开发的测试机器准确地模拟了内部墙壁的加热和冷却过程.
- 69小时后,末端受约束的内壁模型显示累积的相对移位为-244.2毫米,应变为187.8 μm.
- 在卸载前,终端约束力达到最大1.7 MPa,导致混凝土模型的拉伸裂纹.
结论:
- 新型的温度应力测试机有效地模拟了在现实的施工约束下早期的混凝土行为.
- 这些发现提供了关于造内部墙壁应力发展和裂机制的关键数据.
- 这项研究为在冷井建设中开发有效的裂预防策略提供了科学基础.
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