摘要
吉林西部某土坝工程拟建场地地质条件复杂,地基为上部硬土层,下覆湖相淤泥质黏土层,软土层最大埋深约为17.1m,并具有含水率高、压缩性大、排水固结性能差等特点。设计采用无砂垫层真空联合堆载预压方案,但在本区域缺少真空预压施工经验和参考案例,工程面临如下问题:坝基中竖向排水板的压缩变形大,且排水固结时间长,竖向排水板变形后需要具有较好的通水能力和真空传递特性;水平排水管在坝体堆载作用下的竖向应力和差异变形较大,需要较大的环刚度和抗变形能力。本文系统介绍了本工程竖向排水板和水平排水管的材料选型,施工工艺和质量控制要点。对处理后的软土地基进行了长期监测和检测,结果表明:采用排水板联合堆载预压处理湖相淤泥地基,高性能排水材料应用效果较好,地基加固效果良好。本文结果对类似工程具有一定的指导意义。
The proposed site of an earth dam project in the north area has complex geological conditions.The soft soil layer of the foundation is silty clay,overlying by a hard soil layer and the maximum burial depth of the soft soil layer is about 17.1m,and has the characteristics of high water content,high compressibility and poor drainage consolidation performance.Vacuum combined surcharge preloading is selected as ground improvement method,but the local area lack of construction experience and reference cases.The project faces the following difficulties:(1)The deformation of the vertical drains is large,and the consolidation time is long.After large deformation,it needs to have better discharge capacity and vacuum transfer characteristics;(2)The vertical stress and differential deformation of the horizontal drainage material under the dam load are large,which requires large ring stiffness and anti-deformation capacity.This paper systematically introduces the selection of key drainage materials,the construction technology and the quality control points.Long-term monitoring and testing of the treated soft soil foundations were carried out,and the results showed that the high-performance drainage materials played an important role in the treatment of lacustrine clay foundations,and the foundation treatment achieved ideal results.The results of this paper have certain guiding significance for similar projects.
作者
于仲离
占鑫杰
郑澄峰
米占宽
杨守华
Yu Zhongli;Zhan Xinjie;Zheng Chengfeng;Mi Zhankuan;Yang Shouhua(China Water Conservancy and Hydropower first Engineering Bureau Co.,Ltd.,Changchun1300331,Jilin;Institute of Geotechnical Engineering,Nanjing Water Conservancy Research Institute,Jiangsu210029,Nanjing;State key Laboratory of Hydrology,Water Resources and Water Conservancy Project,Nanjing210029,Jiangsu)
出处
《吉林水利》
2022年第12期1-7,共7页
Jilin Water Resources
基金
南京水利科学研究院中央级公益性科研院所基本科研业务费重点项(Y320012)
国家自然科学基金(GK321002)。
关键词
高性能排水材料
湖相淤泥
真空预压
施工工艺
High-performance drainage material
lacustrine deposit
vacuum preloading
construction technology
