兰州大学机构库 >土木工程与力学学院
压实黄土增湿特性及数值模拟研究
Alternative TitleResearch on Moistening and Numerical Simulation of Compacted Loess
熊浏阳
Thesis Advisor谌文武
2015-05-23
Degree Grantor兰州大学
Place of Conferral兰州
Degree Name硕士
Keyword压实黄土 增湿 变形特性 强度特性 数值模拟
Abstract随着西部经济的快速发展,压实黄土广泛应用地基、路堤等工程中,由于管沟渗水、降雨入渗和地下水位的变化等原因,地基或路堤中压实黄土由于增湿,含水量常常会沿宽度和深度方向会发生一定的变化,造成地基或路堤过大的不均匀沉降,从而危害工程的安全。 目前,大部分学者所研究的黄土湿陷问题,主要是关于原状黄土饱和浸水后的湿陷变形和强度问题,而对压实黄土增湿到某一含水量的情况研究相对较少,对青海地区压实黄土研究资料更少,基于此,本文以青海黄土为研究对象,采用固结压缩试验和直剪试验,设计五种干密度为分别1.4g/cm3、1.5 g/cm3、1.6 g/cm3、1.7 g/cm3、1.8 g/cm3,每种干密度分别设计10%、13%、15%、18%、20%的五种增湿含水量的压实黄土进行研究,获得了含水量 和干密度 对试样强度和变形特性的影响,结果表明:压实黄土含水量 一定,干密度 增大,试样的压缩模量 增大;干密度 一定时,含水量 增加,试样的压缩模量 呈指数函数 形式减小。压实黄土干密度 相同,当含水量 增加,试样的粘聚力 呈指数函数 的形式减小,而内摩擦角 呈一次函数 的形式而减小;压实黄土含水量 相同,当干密度 增大时,试样的内摩擦角 一直少量增加,而粘聚力 增大较快且幅度逐渐变大,可以用指数函数 来表示变化规律。 根据固结试验和直剪试验获得变形参数和强度参数,采用FLAC3D软件模拟管沟小量渗水,引起黄土地基的增湿变形,结果表明:对不同干密度的压实黄土地基,在渗水导致的增湿范围内,沉降值变化幅度较大,超增湿范围后,沉降值变化的幅度较小;当干密度小于1.60g/cm3时,提高干密度,可以显著消弱黄土地基由于渗水增湿产生的沉降值和沉降差,当干密度大于等于1.60 g/cm3,提高干密度,消弱效果不明显。
Other AbstractWith the rapid development of western economy, Compacted loess is widely used in the construction of foundation embankment and other projects, so the practical significance of compacted loess. By trench seepage, rainfall infiltration and other reasons make local water content of loess foundation increase, The local soil layer of the foundation reach different moistening water content along width and depth direction, which brings uneven moistening collapse deformation, and make engineering safety. Now, most research on the characteristics of loess deformation, focused predominantly on undisturbed loess, but paid less attention to compacted loess. In this study, with QingHai remolded loess as study object, through direct shear tests and compression test of compacted loess, with the dry density of 1.4、1.5、1.6、1.7、1.8 g/cm3 and water content of 10%、13%、15%、18%、20%, moistening property and deformation property of compacted loess considering influence of water content and dry density, According to the experimental results, compressive modulus of compacted loess increased with the increasing of dry density, the increment of compression of compacted loess first increased then decreased with the increasing of dry density when water content is small, it decreased with the increasing of dry density when water content is large; compressive modulus of compacted loess decreased with the increasing of water content, the amplitude decreased with the increasing of water content; The compressive modulus-water content curves of compacted loess can be expressed with the exponential function , moisture force and friction of compacted loess decreased with the increasing of water content, moisture force-water content can be expressed with the exponential function ,while friction-water content is ; moisture force and friction of compacted loess increased with the increasing of dry density, moisture force-dry density can be expressed with the exponential function . Based on deformation parameters and strength parameters, this paper through FLAC3D to research compacted loess foundation moistening deformation because of trench seepage. it shows the settlement decreased fast in the moistening area, it decreased slow out of the moistening area, When the dry density is less than 1.6g/cm3, increase the dry density can significantly reduce foundation settlement and nonuniform settlement, When the dry density is greater than 1.6g/cm3 greater increase the dry density is ine...
URL查看原文
Language中文
Document Type学位论文
Identifierhttps://ir.lzu.edu.cn/handle/262010/225830
Collection土木工程与力学学院
Recommended Citation
GB/T 7714
熊浏阳. 压实黄土增湿特性及数值模拟研究[D]. 兰州. 兰州大学,2015.
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Altmetrics Score
Google Scholar
Similar articles in Google Scholar
[熊浏阳]'s Articles
Baidu academic
Similar articles in Baidu academic
[熊浏阳]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[熊浏阳]'s Articles
Terms of Use
No data!
Social Bookmark/Share
No comment.
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.