摘要
The expansive clays are extremely sensitive to the slight moisture alteration,exhibiting sequentially volume change.Uneven settlement of the buildings and infrastructures underlying expansive soil is a critical challenge that geotechnical engineers have to deal with.Therefore,the objective of this study is to assess the alteration in the compressibility behavior of expansive clay respecting partial replacement of cement by zeolite in cemented samples.For this purpose,7 and 28 d cured samples treated with 6%,8%,10%,and 12%cement addition and 0,10%,30%,50%,70%,and 90%cement replacement by zeolite were investigated through Atterberg limit and a series of one-dimensional consolidation tests to evaluate the consistency limits and compressibility alteration.The liquid limits of the soil samples indicated a decremental trend as the cement content rose.Afterward,the increase of zeolite replacement up to 30%in each specific cement content diminished liquid limit to its lowest value.Further increment of zeolite replacement increased the liquid limit of the soil-binder mixtures.The lowest plasticity index was also achieved at the 30%zeolite replacement percentage;hence,the lowest swelling potential would be resulted,concerning an indirect classification.The results of the consolidation experimentations disclosed that zeolite replacement had adverse influence on consolidation parameters of cemented samples such as compression index,swell index,coefficient of compressibility,coefficient of volume compressibility,and coefficient of consolidation after 7 d of curing whereas after 28 d of curing,the 30%zeolite-replaced samples represented the best consolidation parameters.Eventually,it can be stated that the addition of cement alongside the partial substitution of cement by zeolite can be a beneficial strategy for the geo-environmental targets of this study.
膨胀黏土对水分的轻微变化极为敏感,表现出连续的体积变化。膨胀土导致的建筑物和基础设施的不均匀沉降是岩土工程师必须应对的一个重要挑战。因此,本研究的目的是评估在膨胀黏土样品中,由沸石部分取代水泥的膨胀黏土的固结行为变化。膨胀黏土中水泥添加量分别为6%,8%,10%,12%以及再用10%,30%, 50%,70%和90%沸石分别代替水泥,以7和28 d的固化样品为研究对象,通过阿特伯格极限和系列一维固结测试评估黏土的稠度极限和固结行为。随着水泥含量的上升,黏土样品的液限呈下降趋势。当沸石替代水泥的量增加到30%时,液限降低到最低。沸石替代水泥进一步增加了黏土的液限。在30%的沸石替换下,塑性指数也最低,涉及到间接分类。固结实验结果表明,沸石替代对黏土样品的压缩指数、膨胀指数、压缩系数、体积压缩系数、固结系数有不利影响,而固化28 d后,30%替代的黏土固结参数最好。研究结果表明,添加水泥并同时用沸石部分替代水泥是有益的。
