冻融与氯盐侵蚀耦合作用下GO-RAC的耐久性能  

Durability of GO-RAC under the Coupling Action of Freeze-Thaw Cycling and Chloride Salt Erosion

作　　者：郭凯[1] 佟舟[1] 张树峰 潘文浩[2] 刘琳[1] GUO Kai;TONG Zhou;ZHANG Shufeng;PAN Wenhao;LIU Lin(School of Civil Engineering,Shenyang Jianzhu University,Shenyang 110168,China;School of Materials Science and Engineering,Shenyang Jianzhu University,Shenyang 110168,China)

机构地区：[1]沈阳建筑大学土木工程学院,辽宁沈阳110168 [2]沈阳建筑大学材料科学与工程学院,辽宁沈阳110168

出　　处：《建筑材料学报》2023年第11期1183-1191,共9页Journal of Building Materials

基　　金：辽宁省自然科学基金资助项目(LJKZ0565)。

摘　　要：通过混凝土抗冻性快冻法试验,研究了氧化石墨烯再生粗骨料混凝土(GO-RAC)在冻融循环与氯盐侵蚀耦合作用下的耐久性能,测试分析了GO-RAC的相对动弹性模量、质量损失率、抗压强度及氯离子侵蚀情况.结果表明:冻融循环与氯盐侵蚀的耦合作用加速了再生粗骨料混凝土(RAC)的劣化损伤,经历72次冻融循环后不同GO掺量GO-RAC的相对动弹性模量均降至其初始值的60%以下,宏观劣化程度较普通RAC有不同程度的降低;由于耦合初期侵蚀产物的填充致密效应,GO-RAC的抗压强度呈现先增大后减小的趋势;GO-RAC在冻融循环与氯盐侵蚀耦合作用下的Cl-分布符合Fick第二定律,表面的Cl-质量比随着耦合次数的增加呈指数形式增大,扩散系数随着耦合次数的增加先减小后增大.The durability performance of graphite oxide recycled coarse aggregate concrete(GO-RAC)under the coupled action of freeze-thaw cycling and chloride ion erosion was tested througth the rapid freezing method of concrete frost resistance.The relative dynamic modulus,mass loss ratio,compressive strength and chloride ion erosion of graphite oxide recycled coarse aggregate concrete were tested and analysed.The results show that the effects of freeze-thaw cycling and chloride erosion exacerbates the damage to the recycled coarse aggregate concrete.After 72 freeze-thaw cycles,the relative dynamic modulus of GO-RAC is reduced to less than 60%of its origin value,but the degree of damage of GO-RAC is reduced to a lesser extent than that of ordinary recycled coarse aggregate concrete(RAC).In the early stages of coupling,the freeze-thaw damage is confined to the surface layer and the erosion products are densely packed,so the compressive strength of GO-RAC shows an initial increasing-and then decreasing trend.The Cl distribution of GO-RAC under the coupling of freeze-thaw cycling and chloride-erosion follows Fick's second law,the surface Cl mass ratio increases exponentially with increasing coupling times,and the diffusion coefficient first decreases and then increases with increasing coupling times.

关 键 词：氧化石墨烯再生粗骨料混凝土 冻融循环 氯盐侵蚀 耦合作用 耐久性 

分 类 号：TU528.572[建筑科学—建筑技术科学]