粉煤灰掺量对直通孔型再生透水混凝土抗盐冻及透水性能的影响  

Influence of fly ash on salt-freezing resistance and permeability of recycled permeable concrete with straight channels

作　　者：夏群[1,2] 赵岑 朱平华[2] 严先萃 王少伟 朱旭东 XIA Qun;ZHAO Cen;ZHU Pinghua;YAN Xiancui;WANG Shaowei;ZHU Xudong(School of Environmental Science and Engineering,Changzhou University,Changzhou 213264,China;School of Urban Construction,Changzhou University,Changzhou 213264,China)

机构地区：[1]常州大学环境科学与工程学院,江苏常州213264 [2]常州大学城市建设学院,江苏常州213264

出　　处：《混凝土》2024年第10期95-99,110,共6页Concrete

基　　金：国家自然科学基金(51878081,52278240);江苏省青年科学基金(BK20220626);常州市领军型创新人才引进培育项目(CQ20210085)。

摘　　要：采用相对动弹模量、抗压强度、透水系数和微观试验,分析了在复杂冻融环境下(5%NaCl、5%Na_(2)SO_(4)和5%NaCl+5%Na_(2)SO_(4))不同粉煤灰掺量(0、10%、20%和30%)对直通孔型再生透水混凝土抗盐冻及透水性能的影响。结果表明:粉煤灰加剧混凝土在5%NaCl溶液中的冻融损伤,适量粉煤灰(10%和20%)可以提高混凝土在5%Na_(2)SO_(4)和5%NaCl+5%Na_(2)SO_(4)溶液下的抗冻效果。经过200次盐冻后,透水系数的结果均大于初始值且满足规范要求。在含硫酸钠的环境中,侵蚀产物在冻融初期有利于增加混凝土基体密实度。直通孔型再生透水混凝土在盐冻环境中具备良好的耐久性能和透水效果,可在复杂盐冻地区推广使用。Using relative dynamic modulus,compressive strength,water permeability coefficient,and micro-test,it analyzed the influence of different fly ash content(0,10%,20%,and 30%)on salt-freezing resistance and permeability of the straight-channel recycled permeable concrete under three freeze-thaw exposure regimes(5%NaCl,5%Na_(2)SO_(4)and 5%NaCl+5%Na_(2)SO_(4)).The test results showed that fly ash aggravated the freeze-thawing damage of concrete in 5%NaCl solution,and the appropriate amount of fly ash(10%and 20%)can improve the frost resistance of concrete in 5%Na_(2)SO_(4)and 5%NaCl+5%Na_(2)SO_(4)solutions.After 200 times of salt-freezing,the results of water permeability coefficient were all greater than the initial value and met the requirements of the specification.Under the regimes containing sodium sulfate,corrosion products were beneficial to improve the compactness of concrete matrix at the early stage of the freeze-thaw cycle.Under salt-freezing regimes,the straight-channel recycled permeable concrete had good durability and pervious effect,and can be popularized and widely used.

关 键 词：透水混凝土 冻融循环 粉煤灰 透水性 

分 类 号：TU528.041[建筑科学—建筑技术科学]