摘要
在我国北方、西北等严寒地区冻融循环是造成混凝土强度损失和结构破坏的主要因素,且混凝土冻融循环损伤过程复杂,其评价机制相对简单,改善措施难于完全满足实际环境需求。基于此,本文对混凝土冻融循环损伤过程进行深入分析,首先对冻融环境下混凝土的破坏机理、冻融试验方法和标准进行归纳与梳理,并对在不同条件下混凝土冻融循环后性能演变规律进行分类和总结,同时概述了利用数值模拟软件对混凝土冻融循环过程进行模拟,最后提出提高混凝土抗冻性的建议和方法。结果表明:冻融循环导致的水相变化是混凝土破坏的关键因素,混凝土内部的孔结构和气泡间距系数对其抗冻融性能起着至关重要的作用。通过提高混凝土强度等级、添加纤维、纳米材料和地聚物等对混凝土改性,优化水灰比、掺入外加剂等方式提高抗冻性能。可为现役混凝土结构的力学特性评估及其耐久性检验提供参考。
In the severe cold areas of northern and northwestern China,the freeze-thaw cycle is the main factor leading to the loss of concrete and structural damage.Moreover,the damage process of concrete caused by freeze-thaw cycles is complex,and its evaluation mechanism is relatively simple,and the improvement measures are difficult to meet the actual environmental needs.Based on this,this paper makes an in-depth analysis of the damage process of concrete caused by freeze-thaw cycles,and firstly summarizes and out the damage mechanism of concrete under freeze-thaw conditions,the test methods and standards of freeze-thaw,and the evolution laws of concrete properties after freeze-thaw under different conditions.At the same time,the simulation of the freeze-thaw cycle process of concrete by using numerical simulation software is outlined,and finally the suggestions and methods to the frost resistance of concrete are proposed.The results show that the water phase change caused by the freeze-thaw cycle is the key factor leading to the damage of concrete,and pore structure inside the concrete and the air bubble spacing coefficient play a vital role in its frost resistance.By improving the concrete strength grade,adding fibers,nano-materials andopolymers,and optimizing the water-binder ratio and adding admixtures,the frost resistance can be improved.It can provide reference for the mechanical property evaluation and durability inspection the existing concrete structure.
作者
王稷良
孟赞
谢来坤
WANG Jiliang;MENG Zan;XIE Laikun(School of Civil Engineering,Hebei University of Engineering,Handan,Hebei 056038,China;Highway Science Research Institute,Ministry of Transport,Beijing 100088,China;Guangxi Guicen Expressway Co.,Ltd.,Nanning,Guangxi 530000,China)
出处
《水利与建筑工程学报》
2025年第4期1-9,共9页
Journal of Water Resources and Architectural Engineering
基金
内蒙古自治区交通运输科技创新项目(NJ-2024-20)。
关键词
混凝土
冻融循环
冻融机理
试验方法
性能演变
数值模拟
concrete
freeze thaw cycles
freezing thawing mechanism
test method
performance evolution
numerical simulation
作者简介
王稷良(1978-),男,博士,研究员,主要从事高性能水泥基材料等方面工作。E-mail:jiliangwang@163.com;通讯作者:孟赞(2001-),男,硕士研究生,研究方向为高性能土木工程材料。E-mail:mengzan0327@163.com。
