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
2013年
z1期
2944-2950
,共7页
桩基础%复合地基%无持力层刺入工况%比较分析%桩长%张拉网%刚性网格%附加桩
樁基礎%複閤地基%無持力層刺入工況%比較分析%樁長%張拉網%剛性網格%附加樁
장기출%복합지기%무지력층자입공황%비교분석%장장%장랍망%강성망격%부가장
pile foundations%composite foundation%case of no bearing stratum penetration%comparative analysis%pile length%stretching net%rigid grid%additional pile
根据刚性桩复合地基和桩承式路堤在有持力层刺入工况下的薄弱部位,分析刚性网格–桩复合地基中张拉网、刚性网格和附加桩对薄弱处的加固作用,研究有、无持力层刺入2种工况下刚性网格–桩复合地基受力和变形在不同桩长影响下的变化特征,对刚性网格–桩复合地基是否适用于无持力层工况进行可行性探讨.研究结果表明:在无持力层刺入工况下,刚性网格–桩复合地基大部分边桩弯矩和剪力较大,当桩长缩小,其分布区域向路堤中心方向扩散;当桩长增加,大部分桩桩体荷载比增大,边桩弯矩及剪力、路堤沉降和路堤外侧竖向变形减小;可通过增加桩长,利用PTC管桩放宽中桩截面,减小附加桩桩径,使刚性网格–桩复合地基实现优化并适用于无持力层刺入工况.
根據剛性樁複閤地基和樁承式路隄在有持力層刺入工況下的薄弱部位,分析剛性網格–樁複閤地基中張拉網、剛性網格和附加樁對薄弱處的加固作用,研究有、無持力層刺入2種工況下剛性網格–樁複閤地基受力和變形在不同樁長影響下的變化特徵,對剛性網格–樁複閤地基是否適用于無持力層工況進行可行性探討.研究結果錶明:在無持力層刺入工況下,剛性網格–樁複閤地基大部分邊樁彎矩和剪力較大,噹樁長縮小,其分佈區域嚮路隄中心方嚮擴散;噹樁長增加,大部分樁樁體荷載比增大,邊樁彎矩及剪力、路隄沉降和路隄外側豎嚮變形減小;可通過增加樁長,利用PTC管樁放寬中樁截麵,減小附加樁樁徑,使剛性網格–樁複閤地基實現優化併適用于無持力層刺入工況.
근거강성장복합지기화장승식로제재유지력층자입공황하적박약부위,분석강성망격–장복합지기중장랍망、강성망격화부가장대박약처적가고작용,연구유、무지력층자입2충공황하강성망격–장복합지기수력화변형재불동장장영향하적변화특정,대강성망격–장복합지기시부괄용우무지력층공황진행가행성탐토.연구결과표명:재무지력층자입공황하,강성망격–장복합지기대부분변장만구화전력교대,당장장축소,기분포구역향로제중심방향확산;당장장증가,대부분장장체하재비증대,변장만구급전력、로제침강화로제외측수향변형감소;가통과증가장장,이용PTC관장방관중장절면,감소부가장장경,사강성망격–장복합지기실현우화병괄용우무지력층자입공황.
According to weak regions of rigid pile composite foundation and piled embankments with bearing stratum penetration,the reinforcement of weak regions by using stretching net,rigid grid and additional pile of rigid gird-pile composite foundation was analyzed. The changing characteristics of force and deformation of rigid grid-pile composite foundation with and without bearing stratum penetration were investigated under different pile lengths;and the feasibility whether the rigid grid-pile composite foundation is applicable to the case without bearing stratum penetration was evaluated. The results show that,without bearing stratum penetration,the bending moment and shear force of most side piles are large,and their distribution regions would increase along the direction of embankment center when the pile length decreases. When the pile length increases,the load ratio of most piles increases,and the bending moment and shear force of side pile,embankment settlement and vertical deformation outside the embankment decrease. By increasing the pile length,applying PTC pile to enlarging the cross-section of central pile,and decreasing the additional pile?s diameter,the rigid grid-pile composite foundation can be optimized and be applicable to the case of bearing stratum penetration.