Scale-Dependent ASR Expansion of Concrete and Its Prediction coupled with Silica Gel Generation and Migration
Scale-Dependent ASR Expansion of Concrete and Its Prediction coupled with Silica Gel Generation and Migration
复制标题
DOI：
10.3151/jact.14.444
复制
发表时间：
2016-08
影响因子：
2
通讯作者：
Yuya Takahashi;S. Ogawa;Yasushi Tanaka;K. Maekawa
中科院分区：
文献类型：
--
作者：
Yuya Takahashi;S. Ogawa;Yasushi Tanaka;K. Maekawa
本研究旨在研究凝胶通过微孔和裂缝迁移对碱硅反应（ASR）引起的混凝土膨胀的影响。首先，通过使用多尺度孔隙力学计算方案对所生产的硅胶进行渗透敏感性分析。然后，发现硅胶运动显着影响混凝土的 ASR 膨胀，其规模效应可能源于硅胶运动时的药物作用力。通过砂浆加速ASR试验，对预测的尺度效应进行了实验验证，并从多尺度力学角度反演了凝胶的渗透作用。这里，还从化学物理以及产生的凝胶迁移的力学角度讨论了碱离子浸出对尺度依赖性的影响。实验中测量的特征尺度依赖性也可以通过涂抹裂纹的非线性分析以及凝胶生成、迁移和碱离子浸出来模拟。
This study set out to investigate the effect of gel migration through micro-pores and cracks on concrete expansion caused by alkali–silica reaction (ASR). First, sensitivity analyses with permeation of produced silica gel were conducted by using a computational scheme of multi-scale poro-mechanics. Then, silica gel movements were found to substantially affect the ASR expansion of concrete with the possibility of its scale effect being rooted in the drugging force when the silica gel is in motion. With accelerated ASR tests of mortar, the predicted scale effects were experimentally verified and the permeation of gel was inversely identified in terms of multi-scale mechanics. Here, the effect of alkali ion leaching on the scale-dependency was also discussed in view of chemo-physics as well as mechanics of produced gel migration. The measured characteristic scale-dependency in the experiment can be also simulated by nonlinear analysis of smeared cracks coupled with gel generation, migration and alkali ion leaching.