ABSTRACT

The Moon Bay City Wall of Sanxingdui is built of pale yellow sand and yellowish brown clay. The yellowish brown layers are suffering severe cracking and spalling. Hence, this paper conducts a specific investigation and performs evaporation and drying–wetting cycle tests on five rectangular specimens with different aspect ratios. The results show that the damage ratio first increases to 50.7% and then declines as the height of the layers rises. The average water content of the layers decreases from 21.8% to 12.8% by increasing the height of the layers. The pattern of the primary crack networks is related to the aspect ratio of the soil blocks. In fact, when the aspect ratio of the blocks is always greater than six, the main crack network has a parallel pattern. When the aspect ratio of the blocks is either greater than six or less than one-sixth, a laddering pattern is possibly created. When the aspect ratio of the blocks equals one, the cracks probably form a polygonal pattern. Moreover, under drying–wetting cycle conditions, the number of the main cracks is basically stable, but the average crack opening increases. A large number of tiny cracks are also formed and propagated rapidly, which further leads to spalling of the soil layers.

摘要

三星堆月亮湾城墙是用淡黄色的沙子和黄褐色的粘土筑成的。黄褐色层正在遭受严重的开裂和剥落。因此，本文进行了具体研究，对五个不同纵横比的矩形试件进行了蒸发和干湿循环试验。结果表明，损伤率先增加到50.7%，然后随着层高的增加而下降。通过增加层高，层的平均含水量从 21.8% 降低到 12.8%。主要裂缝网络的模式与土块的纵横比有关。事实上，当块的纵横比总是大于六时，主裂缝网络具有平行模式。当块的纵横比大于六或小于六分之一时，可能会创建阶梯模式。当块的纵横比等于 1 时，裂缝可能形成多边形图案。此外，在干湿循环条件下，主裂纹数量基本稳定，但平均裂纹开口增加。大量微小裂缝也随之形成并迅速扩展，进一步导致土层剥落。