PDF全文阅读

    何   蕾

          （首都医科大学附属北京友谊医院 ，北京 100050)

摘   要 ：为提高高层建筑筏板基础粉煤灰混凝土的性能 ，设计了四种粉煤灰掺量的混凝土试件 ，对其抗压 强度 、抗氯离子渗透 、抗碳化以及循环试验（冻融循环和干湿循环） 下的损伤特性进行分析。结果表明： 粉煤 灰掺量为 30% 的混凝土试件在 56 d 龄期时抗压强度达到最高 ，为 78 . 5  MPa;  在 60 d 浸泡时间下的电通量增长幅 度最小 ，从 642 C 增加至 964 C ,  表现出最佳的抗氯离子渗透能力 ；同时 ，在 60 d 碳化周期下的碳化深度保持最 低 ，为 9. 7 mm ,  展现出优异的抗碳化性能。因此 ，粉煤灰掺量为 30% 的混凝土试件在抗压强度 、抗氯离子渗透 和抗碳化方面均表现出显著优势 ，可以为类似工程提供参考。

关键词：高层建筑 ；筏板基础 ；粉煤灰 ；混凝土 ；损伤特性 ；抗碳化 ；循环试验 ；电通量

中图分类号：TU528           文献标志码：A            

文章编号： 1005- 8249   (2025)  03- 0058- 06 

DOI:10. 19860/j.cnki.issn1005 - 8249.2025 .03 .011

HE Lei

（Beijing Friendship Hospital，Capital Medical University, Beijing 100050,China）

Abstract: To gain a deeper understanding of the hydrothermal characteristics of low heat Portland cement, the thermodynamic properties and crack resistance of low heat Portland cement were analyzed based on the fly ash content and curing conditions. Prepare concrete test blocks using low heat Portland cement as the base material. Detect the heat release rate, total heat release, and adiabatic temperature rise of the test blocks, and analyze the effects of different curing environments and water cement ratios on the cracking performance of each test block. The results showed that compared with the test blocks prepared with ordinary cement, the test blocks prepared with fly ash combined with low heat Portland cement exhibited significant thermodynamic properties, lower heating rate and first rising and then falling, slower hydration reaction, lower heat release, much lower adiabatic temperature rise than ordinary cement, and better thermodynamic properties. Low-heat Portland cement specimens cured in a constant temperature and humidity environment are less prone to cracking, and specimens with a water cement ratio of 0.6 are also less prone to cracking. Therefore, fly ash composite low heat Portland cement can significantly improve hydration heat performance and suppress cracking under optimized curing conditions and water cement ratio, making it suitable for engineering fields with strict temperature control such as large volume concrete.

Key words: low-heat portland cement; thermodynamics; crack resistance; water-binder ratio

作者简介： 何    蕾  (1985—) ,   女 ，本科 ，工程师 ，研究方

向 ：建筑相关。

收稿日期：2024 - 12 - 31