Akinyemi Banjo A, Bamidele Adeola, Oluwanifemi Adeoye
Farm Structures and Environment Unit, Department of Agricultural and Biosystems Engineering, Nigeria.
Civil Engineering Department, Landmark University Omuaran, Nigeria.
Heliyon. 2019 Jan 31;5(1):e01182. doi: 10.1016/j.heliyon.2019.e01182. eCollection 2019 Jan.
This article is focussed on evaluating the effects of water repellent admixture and different curing regimes on characteristics of clay from termite hills used for production of earth bricks. Water absorption, thickness swelling and compressive strength characteristics of the specimens with different compositions of cement, hydrated lime and water repellent additive subjected to different curing regimes were measured. The samples were characterised by SEM and FTIR. The least water absorption was at 3.3% while thickness swelling ranged from 0.78 to 3.21 % for the samples. Saturated curing condition resulted in an average compressive strength of 35.5 N/mm, cured curing recorded an average value of 32.9 N/mm while dry curing condition produced an average compressive strength of 26.9 N/mm and the wet curing condition resulted in 25 N/mm. SEM characterisation of sample containing 70% termite soil, 30% cement and 0.05 Hydropruf indicated fewer voids, regular and smooth appearance in comparison with others. FTIR analysis showed distinctive broad bands at wave numbers of 3439 cm for O-H stretching, and 1033.83-1008.80 cm for O-H bending for all samples tested. The best performing composition in terms of the dimensional stability test was 70% termite mound clay, 10% cement, 20% hydrated lime and 0.05 Hydropruf additive. The highest mechanical strength was from composition of 70% termite mound clay, 30% cement, no hydrated lime and 0.05 Hydropruf additive. It is concluded that saturated and cured method showed better performance than the wet and dry curing regimes. The termite secretions similarly improved the clay composition in conjunction with cement, lime and chemical admixture in the internal structure of the bricks.
本文着重评估憎水剂和不同养护制度对用于生产土砖的白蚁丘黏土特性的影响。测量了不同水泥、熟石灰和憎水添加剂组成的试样在不同养护制度下的吸水率、厚度膨胀率和抗压强度特性。通过扫描电子显微镜（SEM）和傅里叶变换红外光谱（FTIR）对样品进行了表征。样品的最低吸水率为3.3%，厚度膨胀率在0.78%至3.21%之间。饱和养护条件下的平均抗压强度为35.5 N/mm²，养护养护记录的平均值为32.9 N/mm²，而干燥养护条件下的平均抗压强度为26.9 N/mm²，湿养护条件下为25 N/mm²。对含有70%白蚁土、30%水泥和0.05%Hydropruf的样品进行SEM表征，结果表明与其他样品相比，其孔隙较少，外观规则且光滑。FTIR分析显示，所有测试样品在波数3439 cm⁻¹处有明显的O-H伸缩宽带，在1033.83 - 1008.80 cm⁻¹处有O-H弯曲宽带。在尺寸稳定性测试方面，性能最佳的组合物是70%白蚁丘黏土、10%水泥、20%熟石灰和0.05%Hydropruf添加剂。最高机械强度来自70%白蚁丘黏土、30%水泥、无熟石灰和0.05%Hydropruf添加剂的组合物。得出的结论是，饱和养护和养护方法比湿养护和干养护制度表现更好。白蚁分泌物与水泥、石灰和化学外加剂一起同样改善了砖内部结构中的黏土成分。
