微封装温度升高抑制剂对中型混凝土温度升高的影响

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Yingda Zhang^1,2,3, Junru Zhang¹, Jun Chen³

¹Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031, China.

Materials (Basel, Switzerland)

|March 27, 2025

概括

微封装的温度升高抑制剂 (TRIs) 有效地减少混凝土.

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
建筑技术建筑技术建筑技术

背景情况:

中型混凝土结构 (梁,板块,柱子) 面临热裂风险,由于体积适度和有限的散热.
控制水化温度对于防止这些元素因热应力引起的裂纹至关重要.
传统的大型混凝土策略对于中型元素可能不是最优的.

研究的目的:

研究微封装温度升高抑制剂 (TRIs) 对中型混凝土的水化温度和裂纹抵抗的影响.
确定最佳的TRI剂量,以平衡热性能和机械性能.
阐明TRI减轻热问题的机制.

主要方法:

准备了各种TRI剂量的混凝土混合物 (0%至0.15%).
在绝缘条件下,使用密封泡盒方法监测水化温度的演变.
使用X射线衍射 (XRD),扫描电子显微镜 (SEM) 和机械性能测试 (压缩和拉伸强度).

主要成果:

TRIs显著抑制了峰值水合温度,并延迟了它的开始,具有剂量依赖的效果.
XRD和SEM发现TRIs形成了水化障碍,减缓了CH结晶,改变了CSH凝的演变.
随着TRI的添加,早期的力量下降,但长期的力量恢复被观察到,0.1%的TRI显示最佳性能.

结论:

微封装的TRI提供了一种有效的解决方案,可以减少水化热量,并防止中型混凝土的热裂纹.
0.1%的TRI剂量提供了热缓解和长期机械强度之间的最佳平衡.
控制释放的TRIs的机制是关键,他们的有效性在修改水化水泥.

关键词:

这就是SEM SEM.XRD XRD 在线观看液化温度是指水分的温度.中型混凝土混凝土微封装的TRI是一种TRI.最好的剂量是最优的剂量.热裂解是一种热裂解技术.

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