抛石挤淤机理及其颗粒流数值模拟研究

Mechanism of backfilling rocks to squeeze out ooze and simulated by particle flow code

利用压载挤淤理论对深圳港大铲湾三期陆域形成工程及海口马村港区一期工程抛石挤淤堤挤淤深度进行预测研究,比较挤淤深度计算值与实测值;通过理论分析,提出抛石挤淤机理;采用颗粒流理论(PFC)模拟抛石挤淤的施工过程及施工控制条件;比较相同作业条件下不同淤泥层厚度的挤淤深度关系。研究结果表明:挤淤深度计算值明显小于实测值;抛石挤淤机理不仅仅是压载问题,它还包含块石动能冲击和局部应力集中对挤淤深度的影响;在不同抛填强度、块石直径的挤淤深度,其模拟结果与实测结果基本吻合,一次性抛石量越大;块石直径越大,则挤淤深度越大;淤泥层厚度越大,则挤淤深度也越大。

The replacement depths of the dikes in phase 3 of Dachan Bay Port in Shenzhen and phase 1 of Macun Port in Haikou were calculated with the theory of squeeze out ooze by loading. And the construction process and construction control method were modified with particle flow code theory （PFC）. The mechanism of backfilling rocks to squeeze out ooze was put forward according to all the analysis results. The results show that the replacement depth calculated is less than that measured. According to the modified results, the replacement depths of different amount of backfilling rocks in one time and different rock sizes are different, which is consistent to the measured results in this condition, the bigger amount of backfilling rock in one time, the bigger size of rock, and the deeper of squeezed out ooze. In addition the replacement depths in different ooze thicknesses with the same construction method are different according to the modified results, the disciplinarian is that the replacement depth is along with the depth of the ooze.