摘要
近年来,在真空预压工程中发现排水板附近的细小土颗粒抱团聚集导致排水板淤堵、排水性能急剧降低的现象,即土柱效应。该现象大多发生在处理新近疏浚和吹填淤泥的软基工程中,在天然沉积软土中尚不多见。基于松嫩平原某软基处理工程中遇到的深层软土固结缓慢问题,结合土柱效应开展数值分析,通过对土柱区渗透系数的反演分析给出其衰减系数,认为天然沉积软土在满足特定条件后也会产生土柱效应,其原因在于受软土的高含水率、强流动性、粒径级配与排水板孔径不适配等综合因素的影响。研究结果可为类似工程的地基加固提供借鉴。
In recent years,the phenomenon of clogging of drainage board and sharp reduction of drainage performance due to clumping of fine soil particles around the drainage board has been found in vacuum pre-pressing projects,which is called“soil column effect”.Currently this phenomenon mostly occurs in soft foundation treatment projects dealing with newly dredged and blow-filled silt,and it is not common to see it in naturally deposited soft soils.Based on the slow consolidation of deep soft soils encountered in a soft foundation treatment project in the Songnen Plain,in this study,a numerical analysis is carried out considering the“soil column effect”and the attenuation coefficient is obtained through the inverse analysis of the permeability coefficient in the soil column area.It is concluded that the“soil column effect”can also occur in naturally deposited soft soils when specific conditions are met,which is due to the influence of comprehensive factors such as the high water content of soft soils,strong mobility,and the unsuitability of the particle size gradation and the aperture of the drainage board.
作者
张振
米占宽
朱群峰
占鑫杰
许小龙
ZHANG Zhen;MI Zhankuan;ZHU Qunfeng;ZHAN Xinjie;XU Xiaolong(Nanjing Hydraulic Research Institute,Nanjing 210029,China;Key Laboratory of Reservoir Dam Safety,Ministry of Water Resources,Nanjing 210029,China)
出处
《水利水运工程学报》
CSCD
北大核心
2023年第2期70-79,共10页
Hydro-Science and Engineering
基金
江西省水利厅科技项目(202124ZDKT06)
中央级公益性科研院所基本科研业务费专项资金项目(Y320005)。
关键词
真空联合堆载预压
软基处理
土柱效应
数值模拟
排水固结
vacuum combined surcharge preloading
soft foundation treatment
soil column effect
numerical simulation
drainage consolidation
