聚丙烯酰胺粉煤灰水泥红黏土强度特性

Strength Property of Polyacrylamide Fly Ash Cement Red Clay

利用内蒙古阴山北麓的红黏土,配制单掺聚丙烯酰胺和复掺聚丙烯酰胺及粉煤灰的水泥红黏土,通过无侧限抗压强度和微观试验研究其强度特性。通过室内试验表明,不同配合比均会对水泥红黏土的力学特性产生影响,伴随着聚丙烯酰胺掺量的增加,其强度均呈现先增加后降低的趋势。通过超景深三维显微镜、扫描电子显微镜和X射线衍射试验,对聚丙烯酰胺粉煤灰水泥红黏土的微观孔隙分布、微观形貌结构以及固化机理进行分析,从微观层面对其结构的整体致密性、缝隙发育情况进行判定,得出聚丙烯酰胺粉煤灰水泥红黏土固化机理主要是由水泥水化反应、红黏土与水化产物相互作用、PAM促进效应和粉煤灰促进效应4个方面形成。

By using the red clay distributed in northern Yinshan Mountain of Inner Mongolia,the cement red clay doped with polyacrylamide（PAM） only and doped with the mixture of PAM and fly ash are prepared,whose strength properties are researched by unconfined compressive strength experiment and micro experiment. The laboratory experiment shows that different mixture ratios would make difference in mechanical property of cement red clay,as the proportion of PAM increased,the strength tended to increase at first and then decrease. Through super-depth 3D microscope,scanning electron microscopy and X- ray diffraction tests,the pore distribution,microstructure and curing mechanism of the PAM fly ash cement red clay are analysed,the whole structure compactness and the gap development situation are determined from micro level. It is concluded that the curing mechanism of fly ash cement red clay is formed by the joint action of cement hydration,red clay and hydration products interaction,PAM promoting effect and fly ash promoting effect.