岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2014年
9期
1939-1944
,共6页
陈存礼%蒋雪%杨炯%张洁%薛军秀
陳存禮%蔣雪%楊炯%張潔%薛軍秀
진존례%장설%양형%장길%설군수
土力学%压实黄土%侧限压缩试验%制样含水率%初始结构性参数%压缩性指标
土力學%壓實黃土%側限壓縮試驗%製樣含水率%初始結構性參數%壓縮性指標
토역학%압실황토%측한압축시험%제양함수솔%초시결구성삼수%압축성지표
soil mechanics%compacted loess%confined compression test%molding water content%initial structural parameter%compression indices
对一定试验含水率及干密度下具有不同结构性(排列)的压实黄土试样进行侧限压缩试验,分析制样含水率引起的结构性变化对不同试验含水率压实黄土侧限压缩特性的影响,探讨压缩性指标与初始结构性参数之间的关系。以饱和压实黄土的压缩曲线为基础,通过引入反映结构性影响的初始结构性参数,提出压实黄土压缩曲线的表达式,根据此表达式可以确定湿载耦合时压实黄土的压缩变形。研究结果表明:制样含水率引起的结构性变化对压实黄土的侧限压缩特性有一定的影响,影响程度随试验含水率增大而减小,对饱和压实黄土压缩特性几乎没有影响;压实土的初始结构性随制样含水率的增大或试验含水率的减小而增强,弹性指数基本上不受结构性的影响,结构屈服压力及压缩指数皆随初始结构性参数增大而增大。在不同的试验含水率及制样含水率下,压缩指数及结构屈服压力与初始结构性参数之间皆有良好的归一化非线性关系,且可用以饱和压实黄土的压缩性指标为参照状态的双曲线来描述。
對一定試驗含水率及榦密度下具有不同結構性(排列)的壓實黃土試樣進行側限壓縮試驗,分析製樣含水率引起的結構性變化對不同試驗含水率壓實黃土側限壓縮特性的影響,探討壓縮性指標與初始結構性參數之間的關繫。以飽和壓實黃土的壓縮麯線為基礎,通過引入反映結構性影響的初始結構性參數,提齣壓實黃土壓縮麯線的錶達式,根據此錶達式可以確定濕載耦閤時壓實黃土的壓縮變形。研究結果錶明:製樣含水率引起的結構性變化對壓實黃土的側限壓縮特性有一定的影響,影響程度隨試驗含水率增大而減小,對飽和壓實黃土壓縮特性幾乎沒有影響;壓實土的初始結構性隨製樣含水率的增大或試驗含水率的減小而增彊,彈性指數基本上不受結構性的影響,結構屈服壓力及壓縮指數皆隨初始結構性參數增大而增大。在不同的試驗含水率及製樣含水率下,壓縮指數及結構屈服壓力與初始結構性參數之間皆有良好的歸一化非線性關繫,且可用以飽和壓實黃土的壓縮性指標為參照狀態的雙麯線來描述。
대일정시험함수솔급간밀도하구유불동결구성(배렬)적압실황토시양진행측한압축시험,분석제양함수솔인기적결구성변화대불동시험함수솔압실황토측한압축특성적영향,탐토압축성지표여초시결구성삼수지간적관계。이포화압실황토적압축곡선위기출,통과인입반영결구성영향적초시결구성삼수,제출압실황토압축곡선적표체식,근거차표체식가이학정습재우합시압실황토적압축변형。연구결과표명:제양함수솔인기적결구성변화대압실황토적측한압축특성유일정적영향,영향정도수시험함수솔증대이감소,대포화압실황토압축특성궤호몰유영향;압실토적초시결구성수제양함수솔적증대혹시험함수솔적감소이증강,탄성지수기본상불수결구성적영향,결구굴복압력급압축지수개수초시결구성삼수증대이증대。재불동적시험함수솔급제양함수솔하,압축지수급결구굴복압력여초시결구성삼수지간개유량호적귀일화비선성관계,차가용이포화압실황토적압축성지표위삼조상태적쌍곡선래묘술。
A series of confined compression tests were performed on compacted loess samples of different structures(fabrics) with the same dry density and initial testing water content. The influence of structure caused by different molding water contents on the compressive properties was analyzed for compacted loess with different initial testing water contents. The relationships between the compressibility indices and the initial structural parameter were investigated. The compression curve of saturated compacted loess was regarded as the reference state. The formula of compression curve of unsaturated compacted loess was established to determine the compressive deformation under the coupling of moisture and stress. The test results show that the molding water content has certain influence on the confining compression characteristic of compacted loess,and the extent of the influence decreases with the increase of initial testing water content. The structural influence on compressive deformation of saturated compacted loess is little. The initial structure index of compacted loess increases with increasing of molding water content or decreasing of initial testing water content. The structural change has little influence on the elastic compression indices,but both the structural yield stress and compression indices increase with the increase of initial structural parameter. The relationships of the structural yield stress and the compression indices with the initial structural parameter are normalized well and can be described with hyperbola under different initial testing water contents and molding water contents.