多孔介质中晶体的结晶压力分析  

Crystallization pressure of crystals in porous media

作　　者：周凤玺[1,2] 应赛 蔡袁强[2] ZHOU Feng-xi;YING Sai;CAI Yuan-qiang(School of Civil Engineering,Lanzhou University of Technology,Lanzhou 730050,China;School of Civil Engineering and Architecture,Zhejiang University of Technology,Hangzhou 310014,China;Engineering Research Center for Health Monitoring in Building Life Cycle and Disaster Prevention,Yangtze Normal University,Chongqing 408100,China)

机构地区：[1]兰州理工大学土木工程学院,甘肃兰州730050 [2]浙江工业大学建筑工程学院,浙江杭州310014 [3]长江师范学院建筑物全生命周期健康检测与灾害防治工程研究中心,重庆408100

出　　处：《岩土工程学报》2019年第6期1158-1163,共6页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51868038);甘肃省陇原青年创新创业人才项目

摘　　要：孔隙溶液中结晶体产生的结晶压力是多孔材料宏观上形成介质变形、冻胀破坏的重要因素之一。以溶液–晶体的化学势平衡为基础,考虑了溶液中的粒子相互作用,分别对以过饱和比为驱动的盐分结晶体和以温度为驱动的冰结晶体进行了理论分析,建立了非理想溶液中晶体对孔壁产生的最大结晶压力模型,并对溶液的冰点温度进行了分析。以NaCl溶液和Na2SO4溶液为例,分别对不同浓度和不同温度下的盐、水结晶压力及冰点温度进行了参数分析。结果表明:对于盐分结晶体,其结晶压力与溶液的过饱和比、溶液活度以及结晶盐的类型密切相关;对于冰晶体,其结晶压力与环境温度以及溶液的活度相关。The pressure exerted by growing crystals of salts or water in porous materials is a major factor to induce deformation and freeze-thaw damage. Theoretical derivations for the crystallization pressure of salt crystals driven by supersaturation and ice crystals driven by temperatures are presented based on the chemical potentials of solutions and crystals, in which the ion interaction is taken into account. The models for the maximum crystallization pressure that the growing crystals in non-ideal solution exert on the pore walls are developed. The pressure from crystallization of salts and water as well as the freezing temperature for solutions of aqueous NaCl and Na2 SO4 under different concentrations and temperatures are parametrically analyzed, respectively. The results show that for the salt crystals, the crystallization pressure is closely related to the ratio of supersaturation, solution activity and type of salt crystals;for the ice crystals, the crystallization pressure is related to the ambient temperature and solution activity.

关 键 词：孔隙介质 结晶压力 冰点温度 化学势 

分 类 号：TU43[建筑科学—岩土工程]