Chloride-binding capacity of mortars composed of marine sand subjected to external chloride penetration  

作　　者：Congtao SUN Ming SUN Tao TAO Feng QU Gongxun WANG Peng ZHANG Yantao LI Jizhou DUAN 

机构地区：[1]Key Laboratory of Marine Environmental Corrosion and Bio-fouling,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China [2]School of Civil Engineering,Qingdao University of Technology,Qingdao 266033,China [3]School of Civil Engineering,Hunan University of Science and Technology,Xiangtan 411201,China [4]Open Studio for Marine Corrosion and Protection,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China [5]Nantong Research and Development Center of Marine Science and Technology,Institute of Oceanology,Chinese Academy of Sciences,Nantong 226004,China

出　　处：《Journal of Oceanology and Limnology》2022年第4期1462-1471,共10页海洋湖沼学报（英文）

基　　金：Supported by the Natural Science Key Foundation of Shandong Province(No.ZR2020KE046);the National Natural Science Foundation of China for Exploring Key Scientifi c Instrument(No.41827805);the Basic Science Research Project of Nantong City(No.JC2020125);the Strategic Priority Project of CAS(No.XDA13040402)。

摘　　要：In order to explore the interactional relations of internal chloride and external chloride-binding amongst the cementitious materials,the chloride-binding capacity of mortars composed of marine sand(MS)or washed marine sand(WMS)were investigated.Results indicate that more external chloride can penetrate and diff use more deeply into the WMS mortar than that in the MS mortar.This phenomenon suggests that the external chloride migration resistance due to WMS is lower than that caused by MS.The distribution trends of the bound chloride content in the two types of mortars are the same at diff erent immersion times.However,a signifi cantly decreased area of the bound chloride content exists at the border of the external penetration area(EPA)and the external unaff ected area(EUA)at the immersion ages of 3 and 7 d,and then it disappears gradually with immersion time.The WMS mortar can bind more external chloride,whereas the MS mortar can bind more internal chloride,at diff erent immersion times.The distributions of bound chloride conversion rate in the EPAs of the two types of mortars diff er across immersion times.The distribution fi rstly decreases,and then it increases at the immersion ages of 3 and 7 d.The distribution was from increase,then decreases,and increase again at the immersion ages of 28 and 56 d.The bound chloride conversion rate in the WMS mortar is aff ected more greatly by external chloride penetration than that in the MS mortar.The amounts of the Friedel’s salt tend to increase with prolonged immersion time.Finally,the penetration of external chloride can increase the amount of fi ne capillary pores smaller than 100 nm in the WMSmortar exposed for 56 d in the chloride salt solution(WMS-E)specimen.

关 键 词：marine sand MORTAR chloride binding Friedel’s salt pore structure 

分 类 号：TU528[建筑科学—建筑技术科学]