吹填砂地基排水板堆载预压加固效果三维有限元分析  

Three-dimensional Finite Element Study on Preloading Consolidation of Sand-filled Reclaimed Ground with Prefabricated Vertical drains

作　　者：戚惠峰 毛健智 李义成 陈宏信 QI Huifeng;MAO Jianzhi;LI Yicheng;CHEN Hongxin(Faculty of Infrastructure Engineering,Dalian University of Technology,Dalian,Liaoning116024,China;Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education,Department of Geotechnical Engineering,Tongji University,Shanghai200092,China)

机构地区：[1]大连理工大学建设工程学部,大连116024 [2]同济大学地下建筑与工程系,上海200092

出　　处：《结构工程师》2019年第4期181-189,共9页Structural Engineers

摘　　要：填海造陆工程中的原位淤泥沉积层具有强度低、含水率高、压缩性高等特点。为加速吹填地基的固结,提高其强度,通常使用竖向排水体联合堆载预压的方式进行地基处理。使用有限元方法,对吹填砂地基排水板堆载预压问题进行了研究。建立了排水板地基三维数值模型,考虑了淤泥沉积层的非线性以及井阻效应和涂抹效应,分析了塑料排水板参数和堆载预压参数对加固效果的影响。得到以下结论:加固深度小于排水板长度约1m;排水板布置间距不超过1.4m才能保证将地基土的径向固结度维持在80%;均匀的堆载间隔时间和分级加载量有利于地基的整体安全性。The in-situ mud sediment in reclaimed land is of low strength,high water content and compressibility.Preloading with prefabricated vertical drains (PVDs) is applied to accelerate consolidation of reclaimed land and improve its strength.Finite element method is adopted to investigate preloading consolidation of sand-filled land in this paper.Three-dimensional ground model considering soil nonlinearity of mud sediment,well resistance and smear effect is developed first.The influences of design parameters of PVD and loading on consolidation are then analyzed.Main conclusions are drawn as follows:reinforced depth is1 m smaller than the length of PVD.The spacing of PVD should be smaller than1.4 m to guarantee 80% degree of radial consolidation.Uniform loading interval and magnitude of loading of each step is beneficial to the safety of the ground.

关 键 词：填海造陆 固结 堆载预压 竖向排水体 数值模型 

分 类 号：TU472.33[建筑科学—结构工程]