Investigation of concrete exposed to dual sulfate attack
Investigation of concrete exposed to dual sulfate attack
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DOI：
10.1016/j.cemconres.2014.06.002
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发表时间：
2014-10-01
影响因子：
11.4
通讯作者：
Soliman, A. M.
中科院分区：
文献类型：
--
作者：
Nehdi, M. L.;Suleiman, A. R.;Soliman, A. M.
暴露于硫酸盐的混凝土的耐久性主要是在完全浸没在硫酸盐溶液中的试样上进行研究的。然而，现场经验表明，暴露于硫酸盐的混凝土可能会因物理侵蚀而在地面以上产生表面结垢。这种损害常常被忽视，甚至与化学硫酸盐侵蚀混淆。在这项研究中，混凝土部分浸泡在硫酸盐溶液中，并暴露于循环温度和相对湿度进行了探讨。结果表明，混凝土可以经历双重硫酸盐侵蚀。下部浸没部分可能遭受化学硫酸盐侵蚀，而上部可能易受物理侵蚀。降低水与粘合剂的比例和水固化减少了溶液水平以上的表面结垢，因为孔的体积减少了。虽然用火山灰部分替代水泥也降低了孔隙体积，但由于小直径孔隙的比例增加以及毛细管吸力和蒸发表面积的相关增长，表面结垢增加。(C)2014爱思唯尔有限公司版权所有。
Durability of concrete exposed to sulfates has primarily been studied on specimens fully-submerged in sulfate solutions. However, field experience shows that concrete exposed to sulfates can suffer from surface scaling above ground level due to physical attack. This damage has often been ignored and even confused with chemical sulfate attack. In this study, concrete partially-immersed in sulfate solutions and exposed to cyclic temperature and relative humidity was explored. Results show that concrete can experience dual sulfate attack. The lower immersed portion can suffer from chemical sulfate attack, while the upper portion can be vulnerable to physical attack. Lowering the water-to-binder ratio and moist-curing reduced surface scaling above the solution level, since the volume of pores was decreased. Although partial replacement of cement with pozzolans also decreased the pore volume, surface scaling increased due to increased proportion of small diameter pores and associated growth of capillary suction and surface area for evaporation. (C) 2014 Elsevier Ltd. All rights reserved.