一个新的负载共享系统,在实际情况下模拟应变硬化水泥复合材料 (SHCC) 的爬行
Karuna Arachchige Shan Dilruksha Ratnayake1, Christopher Kin Ying Leung1
1Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Hong Kong SAR, China.
Materials (Basel, Switzerland)
|May 25, 2024
概括
应变硬化混凝土复合材料 (SHCC) 显示出对基础设施的有希望的耐用性. 这项研究发现,SHCC在外部应用到混凝土的经验中,在持续负荷下裂的扩大比以前认为的要少,从而确保了长期的保护.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 结构工程 结构工程
背景情况:
- 应变硬化水泥复合材料 (SHCC) 由于其受控的裂纹行为,在民用基础设施中提供了更好的耐用性.
- 人们担心,在持续负荷下,SHCC的裂会扩大,这可能会损害长期性能.
- 现实世界中的结构应用涉及负载共享,与实验室的持续负载条件不同.
研究的目的:
- 为了研究SHCC作为钢筋混凝土上的外部层的爬行行为.
- 在现实的负载共享条件下,评估SHCC的依赖时间的裂扩大.
- 开发一种模拟方法,用于钢筋混凝土-SHCC系统中的应力-延展模式.
主要方法:
- 开发了一种新的负载共享固定装置,以模拟钢筋和SHCC之间的持续时刻转移.
- 随着时间的推移,对强化和SHCC的应力进行了监测.
- 在SHCC层中应变和裂宽度被仪器仪表和监测.
主要成果:
- 在SHCC层中,时间依赖的裂扩大明显比在持续负荷下不那么严重.
- 负载共享系统允许详细监测时间依赖的材料反应.
- SHCC对水和化学物质透的抗性可能会长期保持.
结论:
- 在钢筋混凝土上作为外部层应用的SHCC在持续的,共享的负载下减少了裂扩大.
- 开发的模拟方法为了解SHCC爬行行为提供了有价值的数据.
- 研究结果支持SHCC在民用基础设施应用中的长期耐用性益处.
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