Abstract: With the continuous increase of shipping demand and the deepening promotion of the concept of smart waterway, the task of waterway construction and maintenance becomes increasingly complex and challenging. In channel dredging engineering, the quality of soil has a significant impact on engineering quality and investment. Especially, the presence of hard clay can easily cause difficulties in excavation, pilling and pipe blockage. Statistical analysis was conducted on hard clay encountered in domestic and foreign projects, and typical mechanical indicators of hard clay were obtained. The impact compaction combined with electro-osmotic consolidation method was used for remolding, and the large-scale experimental soil similar to natural hard clay was obtained, which played a certain role in the research of dredging equipment and technology for hard clay. Analysis results show that the combined remolding method can effectively prepare hard clay in a short period of time, and the standard penetration test (SPT) blow of the remolded soil can reach 20 blows. The electro-osmotic method can further enhance the consolidation effect of the soil, with the intermittent reversal voltage method showing optimal results. It is essential to fully consider the influence of overlying stress and water level changes on the standard penetration test blow of the remolded soil during the experiment.

Key words: waterway engineering; dredging engineering; hard clay; combined remolding; standard penetration test; electro-osmosis consolidation

摘要： 随着航运需求的不断增加以及智慧航道理念的深入推广，航道建设与维护的任务愈发地复杂和艰巨。在航道疏浚工程中，疏浚土质对工程质量及投资有着显著影响，而硬质黏土的存在则极易导致挖掘困难、起球堵管等问题。针对国内外项目中遇到的硬质黏土进行统计分析，得出了硬质黏土的典型力学指标，并采用冲击密实联合电渗固结法对其进行重塑，得到了与天然硬质黏土相似的大型试验用土，为疏浚机具及疏浚工艺处理硬质黏土的研究提供了一定作用。分析结果表明：联合重塑法可在较短时间内有效制备硬质黏土，重塑土体的标准贯入击数可达20击；电渗法可进一步增强土体加固效果，其中间歇反转电压效果最佳；在试验过程中，需要充分考虑上附土体压载和水位变化对重塑土体标准贯入击数的影响。

关键词: 航道工程；疏浚工程；硬质黏土；联合重塑；标贯击数；电渗固结