Chatveera B, Lertwattanaruk P
Department of Civil Engineering, Faculty of Engineering, Thammasat University, Rangsit Campus, Khlong Luang, Pathumthani 12121, Thailand.
Faculty of Architecture and Planning, Thammasat University, Rangsit Campus, Khlong Luang, Pathumthani 12121, Thailand.
J Environ Manage. 2014 Jan 15;133:365-73. doi: 10.1016/j.jenvman.2013.12.010. Epub 2014 Jan 9.
This paper presents the performance of cement mortar containing black rice husk ash (BRHA) under nitric and acetic acid attacks. The BRHA, collected from an electrical generating power plant that uses rice husk as fuel, was ground using a grinding machine. The compressive strength loss, weight loss, and expansion of mortars under nitric and acetic acid attack were investigated. The test results of BRHA properties in accordance with the ASTM C 618 standard found that the optimal grinding time was 4 h as this achieved a Blaine fineness of 5370 cm(2)/g. For parametric study, BRHA were used as a Portland cement Type 1 replacement at the levels of 0%, 10%, 20%, 30%, 40%, and 50% by weight of binder. The water-to-binder ratios were 0.55, 0.60, and 0.65. From test results, when the percentage replacements of BRHA in cement increased, it was observed that the strength loss and weight loss of mortars containing BRHA under acetic acid attack were higher than those of the mortars against nitric acid attack. It was found that, of the various BHRA mortars, the strength loss and weight loss due to nitric and acetic acid attacks were the lowest in the mortar with 10% BRHA replacement. For 10%, 20% and 30% BRHA replacements, the rate of expansion of the BRHA mortar decreased when compared with the control mortar. For the mortars with other percentage replacements of BRHA, the rate of expansion increased. Furthermore, the effective water-to-binder ratios of control and BRHA mortars were the primary factor for determining the durability of mortar mixed with BRHA.
本文介绍了含黑米稻壳灰（BRHA）的水泥砂浆在硝酸和乙酸侵蚀下的性能。从以稻壳为燃料的发电厂收集的BRHA，用研磨机进行研磨。研究了水泥砂浆在硝酸和乙酸侵蚀下的抗压强度损失、重量损失和膨胀情况。根据ASTM C 618标准对BRHA性能进行测试的结果发现，最佳研磨时间为4小时，此时勃氏比表面积达到5370平方厘米/克。在参数研究中，BRHA按占胶凝材料重量的0%、10%、20%、30%、40%和50%的比例替代I型波特兰水泥。水胶比分别为0.55、0.60和0.65。从测试结果可知，随着水泥中BRHA替代百分比的增加，含BRHA的水泥砂浆在乙酸侵蚀下的强度损失和重量损失高于在硝酸侵蚀下的情况。结果发现，在各种BRHA水泥砂浆中，10% BRHA替代量的砂浆因硝酸和乙酸侵蚀导致的强度损失和重量损失最低。对于10%、20%和30%的BRHA替代量，与对照砂浆相比，BRHA水泥砂浆的膨胀率降低。对于其他BRHA替代百分比的砂浆，膨胀率增加。此外，对照砂浆和BRHA水泥砂浆的有效水胶比是决定掺BRHA砂浆耐久性的主要因素。
