西藏高寒地区碾压混凝土大坝低热硅酸盐水泥和F-N掺合料应用研究

Applied research of low-heat portland cement and F-N admixtures for RCC DAMS in Xizang Region

摘要

目前碾压混凝土筑坝胶凝材料多采用中热水泥高掺粉煤灰，以降低大坝混凝土内部温升，达到温控防裂的目的。西藏地区由于工业水平较低和交通条件限制，缺少粉煤灰、矿渣等优质掺合料，但当地拥有大量的天然火山灰资源，如果能够加以利用，部分或全部替代粉煤灰掺合料，将能够很好地解决粉煤灰短缺，供应成本高的问题。研究了传统的中热水泥单掺F以及低热水泥单掺F、复掺F-N、单掺N等不同方案的碾压混凝土性能，结果表明低热水泥复掺F-N掺合料的碾压混凝土各项性能满足设计要求，后期强度和抗冻性能优于中热水泥单掺F。

Abstract

At present, the cementing materials of RCC damming mostly use medium heat cement with high fly ash to reduce the internal temperature and achieve the purpose of temperature control and crack prevention. Xizang lacks high-quality admixtures such as fly ash and slags, but there are a large number of natural volcanic ash resources. If they can be used to partially or completely replace fly ash, the problem of fly ash shortage and high supply cost will be solved. The performance of RCC with different schemes, such as medium hot cement mixed with fly ash, low hot cement mixed with fly ash, mixed F-N and single N is studied The result show that the performance of RCC with low heat cement mixed with F-N admixtures meets the design requirements, long-term strength and frost resistance are better than the medium heat cement mixed with F.

关键词

大坝 / 碾压混凝土 / 低热水泥 / FN掺合料 / 粉煤灰

Key words

dam / roller compacted concrete / low heat cement / F-N admixture / fly ash

Author summay

吴文博(1991—), 男, 高级工程师, 硕士, 主要从事水工混凝土研究工作。E-mail: [e-mail]