Evaluation system on water transport properties of cracked concrete under environmental conditions

2015 Fiscal Year Final Research Report

• Project/Area Number: 26820175
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Civil engineering materials/Construction/Construction management
• Research Institution: Saitama University
• Principal Investigator: LUAN Yao 埼玉大学, 理工学研究科, 助教 (20725288)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: コンクリート / ひび割れ / 水分移動 / 二相系モデル / 撥水材

Outline of Final Research Achievements

In this research, water transport properties of cracked cementitious materials were studied. First, water absorption experiment was conducted, with different crack widths, absorption directions and saturation degrees before absorption. Second, a two-phase transport model was established and the water absorption of ECC materials with different crack conditions were analyzed numerically. Since crack becomes convenient channel for water ingression from cracks to cement matrix, the absorption process was greatly accelerated. Such an accelerated process was well reproduced using the model. Then, mortars with internal hydrophobicity were made. Based on absorption experiment, it is confirmed that the specimens with surface coating, when crack occurred, lost their water repellency, whereas the internal hydrophobized specimens remained water repellent state. Therefore, the internal hydrophobized mortar is promising to be used in practice.

Free Research Field

工学