ABSTRACT

The brick-earth foundation of the Bell Tower in Xi’an, which has been preserved for about 600 years since the Ming Dynasty, has suffered from different degrees of infiltration and leakage from rainfall, caused by the ageing and cracking of the anti-seepage layer (cement mortar, lime soil and asphalt felt) on the top of the foundation and the loss of clay particles in the rammed soil. In order to address this problem, two common seepage control measures were evaluated by using laboratory tests and model tests, one by replacing the modified soil and the other by compacting the rammed earth. For the former, the shear strength, permeability, and microstructural properties of six types of modified soils were studied when using traditional modified soil for reclamation. Anti-seepage effects of modified soils were compared through four characteristic parameters such as maximum increment of volumetric water content, residual volumetric water content, the infiltration duration, average increment rate. Adding sticky rice juice, lime water and tung oil into the plain soil (PS) or tabia is an optimal option. For the latter, it is difficult to achieve a good anti-seepage effect only by increasing the density of rammed earth. Thus, it is recommended to use the optimal soil modification option as the anti-seepage measure.

摘要

西安钟楼的砖土基础，自明代以来已经保存了约600年，由于防渗老化和开裂，遭受了不同程度的雨水渗漏。层（水泥砂浆、石灰土和沥青毡）在基础顶部和夯土中粘土颗粒的损失。为了解决这个问题，通过实验室试验和模型试验对两种常见的防渗措施进行了评估，一种是更换改良土壤，另一种是压实夯土。对于前者，研究了使用传统改良土进行复垦时六种改良土的抗剪强度、渗透性和微观结构特性。通过体积含水量最大增量、剩余体积含水量、入渗持续时间、平均增量率4个特征参数比较改性土的防渗效果。将糯米汁、石灰水和桐油添加到普通土壤 (PS) 或塔比亚中是最佳选择。对于后者，仅通过增加夯土的密度很难达到良好的防渗效果。因此，建议使用最佳土壤改良方案作为防渗措施。仅通过增加夯土的密度很难达到良好的防渗效果。因此，建议使用最佳土壤改良方案作为防渗措施。仅通过增加夯土的密度很难达到良好的防渗效果。因此，建议使用最佳土壤改良方案作为防渗措施。