混凝土中毛细压力饱和度关系模型

Model on Capillary Pressure saturation Relationship for Concrete

摘要:

首先分析了混凝土中毛细压力产生的原因，进一步分析了毛细压力与孔隙内水分弯液面之间的相关关系以及毛细压力与相对湿度之间的联系.利用圆柱孔模型对排湿过程同一相对湿度对应饱和度比吸湿过程高这种滞后效应进行分析.根据滞后效应的分析，基于已有的吸湿过程中毛细压力与饱和度关系提出了预测排湿过程中毛细压力与饱和度之间的关系模型.进一步引入等比容吸附热量的影响，分析了温度对排湿过程中毛细压力与混凝土内饱和度之间关系的影响，结果发现随着温度的升高同样饱和度对应的毛细压力数值逐渐降低.

Abstract:

The paper presents an analysis of the cause to the capillary pressure. Then, the paper explores the relationship between the capillary pressure and the curved liquid water surface in pores and the relationship between the capillary pressure and relative humidity, respectively. Hysteresis effect occurs in desorption process in comparison with that absorption process, and the reason is illustrated by using cylindrical holes. A prediction model for the relationship between capillary pressure and saturation in desorption process is therefore set up on the basis of the hysteresis effect. Finally, an analysis is made of the influence of temperature on relationship between capillary pressure and saturation with a consideration of the adsorption isosteric heat effect. Analysis results show that with the rising of the temperature, the capillary pressure gradually reduces at the same saturation.