煤田地质与勘探
煤田地質與勘探
매전지질여감탐
COAL GEOLOGY & EXPLORATION
2012年
6期
58-62
,共5页
杨爱武%刘琦%闫澍旺%杜东菊
楊愛武%劉琦%閆澍旺%杜東菊
양애무%류기%염주왕%두동국
吹填软土%结构性%流变%等时曲线
吹填軟土%結構性%流變%等時麯線
취전연토%결구성%류변%등시곡선
soft dredger fill%structure%creep%isochronous curve
软土普遍存在结构性,结构性影响土体各种力学行为.对天津滨海新区结构性吹填软土进行三轴流变试验,通过对比分析原状土与重塑土流变等时曲线发现,结构性吹填软土流变等时曲线可分离为线性粘弹性变形、线性粘塑性变形与非线性粘塑性变形.在应力小于结构屈服应力时,流变等时曲线线刚度大;超过结构屈服应力时,伴随着土结构的破损,流变等时曲线线刚度逐渐减小,最终趋于一定值,与重塑土接近.结构性对流变等时曲线的影响主要集中在线弹性阶段,进入塑性阶段后影响较小.
軟土普遍存在結構性,結構性影響土體各種力學行為.對天津濱海新區結構性吹填軟土進行三軸流變試驗,通過對比分析原狀土與重塑土流變等時麯線髮現,結構性吹填軟土流變等時麯線可分離為線性粘彈性變形、線性粘塑性變形與非線性粘塑性變形.在應力小于結構屈服應力時,流變等時麯線線剛度大;超過結構屈服應力時,伴隨著土結構的破損,流變等時麯線線剛度逐漸減小,最終趨于一定值,與重塑土接近.結構性對流變等時麯線的影響主要集中在線彈性階段,進入塑性階段後影響較小.
연토보편존재결구성,결구성영향토체각충역학행위.대천진빈해신구결구성취전연토진행삼축류변시험,통과대비분석원상토여중소토류변등시곡선발현,결구성취전연토류변등시곡선가분리위선성점탄성변형、선성점소성변형여비선성점소성변형.재응력소우결구굴복응력시,류변등시곡선선강도대;초과결구굴복응력시,반수착토결구적파손,류변등시곡선선강도축점감소,최종추우일정치,여중소토접근.결구성대류변등시곡선적영향주요집중재선탄성계단,진입소성계단후영향교소.
Soft soil has structural characteristics which affect its mechanical behavior. In this paper, triaxial rheological test was conducted for structural soft dredger fill in Tianjin Binhai new area. Through comparative analysis of undisturbed and remolded soil rheological isochronous curve we knew that the rheological isochronous curve of the structural soft dredger fill can be divided into linear visco-elastic behavior, linear visco-plastic defor-mation and nonlinear visco-plastic deformation. When stress is less than structure yielding stress, rheological isochronous curve linear rigidity is larger;conversely, with the soil structure damaged, it turned to smaller, finally tended to be a certain value approaching to remolded soils. The structure affects rheological isochronous curve is mainly in linear elastic stage and smaller in plastic stage.