|Table of Contents|

Analysis of calcium leaching process and porosity change of mortar under environment of soft water

《南京理工大学学报》（自然科学版）[ISSN:1005-9830/CN:32-1397/N]

Issue:
2016年03期
Page:
366-
Research Field:
Publishing date:

Info

Title:
Analysis of calcium leaching process and porosity change of mortar under environment of soft water
Author(s):
Yu Jian; Zuo Xiaobao; Tang Yujuan
School of Science,Nanjing University of Science and Technology,Nanjing 210094,China
Keywords:
soft water environment;  cement;  mortar;  calcium leaching;  porosity;  Fick's law;  Gerard's solid-liquid equilibrium equation;  Ca(OH)2;  weighing method
PACS:
TU528.01
DOI:
10.14177/j.cnki.32-1397n.2016.40.03.020
Abstract:
To get the effective experimental data of calcium leaching process for cement based material quickly,a model of calcium leaching of mortar in cylinder specimens under an environment of soft water is established using Fick's law and Gerard's solid-liquid equilibrium equation.Computing methods of porosity and Ca(OH)2 content for mortar in the leaching process are presented.Experiments on the accelerated leaching of the mortar specimens immersed into 6M NH4Cl solution with different water-cement ratio are carried out.A changing law of the porosity of these mortar specimens with leaching time is obtained by the weighing method.The porosities calculated by the model are compared with the experimental results to validate the model.The space-time changes of the porosity and Ca(OH)2 content of the mortar specimens are analyzed numerically.The results show that:the model is consistent with the experiments; in the scope of the leaching depth of the mortar specimens,the porosity increases with the leaching time,and the porosity of the surface for the mortar specimens increases rapidly in the initial stage of the leaching time; but the Ca(OH)2 content decreases with the increase of the leaching time,and decreases quickly at the beginning of leaching.

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Last Update: 2016-06-30