基于等温吸附的水泥基孔隙材料水分传输过程  

Moisture Transport Based on Water Vapor Sorption Isotherm of Cement-based Porous Materials

作　　者：张东东[1] 庞晓贇 李克非[1] 

机构地区：[1]教育部土木工程安全与耐久重点试验室清华大学土木工程系,北京100084

出　　处：《硅酸盐学报》2015年第8期1024-1031,共8页Journal of The Chinese Ceramic Society

基　　金：国家重点基础研究发展计划(2009CB623106);国家自然科学基金项目(51378295)资助

摘　　要：讨论了水泥基孔隙材料水分传输的主要机理,建立了孔隙水分传输的多相和简化模型。测试了胶凝材料含有70%矿渣的净浆和砂浆材料的等温吸附与脱附曲线(WVSI),得到了孔隙材料的水分特征曲线。利用水分传输模型对等温吸附实验脱附过程的实验数据进行回归,得到材料的本征渗透率。结果表明:在相对湿度h=60%时,两个模型的回归结果相近;在相对湿度h=18%时,两个模型的回归结果相差较大;简化模型仅适用于中等湿度(h=60%)及以上环境中水分传输过程的描述;基于等温吸附曲线数据,利用模型回归水泥基材料本征渗透率的方法基本可行。The mechanisms on water transport in porous cement-based materials were investigated. The simplified and multi-phase models for moisture transport were proposed. The water vapor sorption isotherms(WVSI) were measured for cement pastes and mortars containing 70% GGBS in binder. The WVSI curves are converted to water characteristic curves and the intrinsic permeability of cement-based materials is regressed from the desorption process in the WVSI measurement. The results show that the simplified model and multi-phase model obtain the similar values of permeability for desorption when humidity(h)=60% while the regression values of permeability for desorption at h=18% have notable differences between the two models. The simplified model is valid for water transport at a moderate humidity(i.e., h=60%) and above. The method of determining intrinsic permeability from WVSI and moisture transport model is feasible for the indirect measurement in laboratory.

关 键 词：水泥基材料 水分传输 本征渗透率 等温吸附 

分 类 号：TQ531[化学工程—煤化学工程]