高原湖相泥炭土固结系数变化规律试验研究  

Experimental study of the change law of consolidation coefficient of the plateau lacustrine peaty soil

作　　者：桂跃[1] 余志华[1] 刘海明[1] 曹净[1] 王兆昌 

机构地区：[1]昆明理工大学建筑工程学院,云南昆明650051 [2]中国有色金属工业昆明勘察设计研究院,云南昆明650051

出　　处：《岩石力学与工程学报》2016年第A01期3259-3267,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51568030);河海大学岩土力学与堤坝工程教育部重点实验室开放基金项目(GH201401)~~

摘　　要：基于大量室内试验结果,系统分析高原湖相泥炭土一维固结特性,探讨取样深度、固结压力p、加荷比R、加荷方式和预压荷载等因素对固结系数Cv的影响及机制。试验结果表明:泥炭土重塑和原状样Cv均满足随p增大而迅速减小之后趋于稳定的规律,和普通黏性土差异较大;经过预压的泥炭土,当预压荷载≤100 k Pa时,其Cv-p关系和未预压样基本一致;预压荷载>100 k Pa时,Cv较未预压样大幅度减小,并且随着p的增大,Cv变化不大;当固结压力p>200 k Pa后,所有经过预压土样和未预压样的Cv值大小相近。分析表明:原状样结构性不显著是造成泥炭土固结特性的主要原因;固结压力作用下,泥炭土经历了从多孔隙状态至相对密实状态的转变。Based on a series of test results, the one-dimensional consolidation coefficient and consolidation mechanism of plateau lacustrine peaty soil from Kunming and Dali city were studied, and some factors, such as the depth of sampling, consolidation pressure（p）, loading method, loading ratio（R） and preloading were discussed. Test results showed that the consolidation coefficients（Cv） of peaty soil decreased with increasing of consolidation pressure firstly, then reduced slowly and stably. The relationship between the consolidation pressure and the consolidation coefficients of peaty soil was a power regression. Under preloading, the consolidation coefficients of peaty soil were pretty much exactly the same as the nature sample when preloading was lower than 100 kPa. It was lower than the nature sample once the preloading was larger than 200 kPa. When consolidation pressure was larger than 200 kPa, consolidation coefficients of peaty soil changed little with consolidation pressure increased. The mechanisms of consolidation were analyzed, which caused the peculiar consolidation properties was rarely structural strength of natural peaty soil. With consolidation pressure increasing, peaty soil changed from porous to relatively dense state.

关 键 词：土力学 泥炭土 一维固结系数 预压 渗透系数 孔隙比 

分 类 号：TU43[建筑科学—岩土工程]