风积沙分布在世界各地,表现出不良的分级,低凝聚力,和松散的结构。沙漠地区的基础设施建设有时需要稳定沙子,以水泥为主固化剂。本研究首先采用正交实验来评估关键因素,例如,固化时间,水泥用量,和水的剂量,影响水泥稳定风积砂的无侧限抗压强度(UCS)。上述每个因素都被设置为五个级别,即固化时间(7、14、28、60和90天),水泥用量(3%,5%,7%,9%,和11%),和水用量(3%,6%,9%,12%,和15%),分别。水和水泥用量为天然风沙质量的百分比。结果表明,影响ASCUCS的敏感性因素是水泥用量,固化时间,和水的用量按降序排列。ASC的UCS与养护时间和水泥用量呈正相关,随着水用量的增加,它先增加后减少。最佳条件为90天固化时间,水泥用量11%,和9%的水剂量。使用光学显微镜对ASC进行显微分析,扫描电子显微镜(SEM),和X射线衍射(XRD)表明,水化产物通过粘结松散颗粒和填充孔隙来增强强度,从而提高压实度。风积-水泥反应体系中水化产物的数量和密实度随着水泥用量和养护时间的增加而增加,低水用量抑制了水化反应。这项研究可以为风积沙的稳定机理提供见解,帮助沙漠地区的基础设施建设。
Aeolian sand is distributed worldwide, exhibiting poor grading, low cohesion, and loose structure. Infrastructure construction in desert areas sometimes requires stabilization of the sand, with cement as the primary curing agent. This study first employed orthogonal experiments to evaluate critical factors, e.g., curing time, cement dosage, and water dosage, affecting the unconfined compressive strength (UCS) of the aeolian sand stabilized with cement (ASC). Each of the aforementioned factors were set at five levels, namely curing time (7, 14, 28, 60, and 90 days), cement dosage (3%, 5%, 7%, 9%, and 11%), and water dosage (3%, 6%, 9%, 12%, and 15%), respectively. The water and cement dosages were percentages of the mass of the natural aeolian sand. The results indicated that the sensitivity of the influencing factors on the UCS of ASC was cement dosage, curing time, and water dosage in descending order. The UCS of ASC positively correlated with curing time and cement dosage, while it first increased and then decreased with the water dosage increase. The optimal conditions were 90 days\' curing time, 11% cement dosage, and 9% water dosage. The microscopic analyses of ASC using optical microscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) revealed that hydration products enhanced strength by bonding loose particles and filling pores, thereby improving compaction. The quantity and compactness of hydration products in the aeolian-cement reaction system increased with the increases in cement dosage and curing time, and low water dosage inhibited the hydration reaction. This study can provide insights into the stabilization mechanism of aeolian sand, aiding infrastructure development in desert regions.