欠固结土体自重固结沉降特性模拟分析

发布时间：2018-03-07 19:04

本文选题：土体自重固结　切入点：孔隙水压力　出处：《南京理工大学》2013年硕士论文　论文类型：学位论文

【摘要】：针对土体自重固结造成的地基不均匀沉降和桩基负摩阻力问题,采用数值模拟方法,对具有不同密度和不同渗透系数的欠固结土体自重固结沉降过程进行模拟分析,主要研究(1)土体密度和土体渗透系数对土体固结沉降过程中孔隙水压力消散影响；(2)土体密度和土体渗透系数对土体固结沉降过程中土压力的增长的影响；(3)土体密度和土体渗透系数对土体自重固结过程中的固结沉降变形的影响。通过对模拟结果的分析,获得了 (1)土体自重固结过程中孔隙水压力的消散规律土体自重固结时,初始超孔隙水压力随着密度的增加而增加,二者呈线性关系；超孔隙水压力消散速度随着渗透系数的增大而增大；自重固结过程中,超孔隙水压力消散经历了缓慢加速消散、快速消散和减速缓慢消散阶段。固结过程中超孔隙水压力消散与时间的关系可以用式(3-2)来描述。 (2)土体自重固结过程中土压力的增长规律土体自重固结时,土压力随着密度的增加而增加,二者呈线性关系；土压力的增长速度随着渗透系数的增大而加快。自重固结过程中,土压力随固结时间的增长规律包括缓慢加速增长、快速增长和减速缓慢增长阶段,其消散规律可以用式(4-3)进行描述。 (3)土体自重固结过程中固结沉降变形发展规律土体自重固结时,固结沉降量随着密度的增加而增加,二者呈线性关系；固结沉降的增长速度随着渗透系数的增大而加快。自重固过程中,固结沉降量随固结时间的增长可分为缓慢加速沉降、快速沉降和减速缓慢沉降阶段,其固结沉降随时间的发展规律可以用式(5-3)进行描述。
[Abstract]:Aiming at the problem of uneven settlement of foundation and negative friction of pile foundation caused by self-consolidation of soil mass, the process of self-consolidation settlement of underconsolidated soil with different density and permeability coefficient is simulated and analyzed by numerical simulation method. Effect of soil density and permeability coefficient on pore water pressure dissipation during consolidation and settlement. Influence of degree of soil permeability and soil permeability on consolidation settlement deformation during self-gravity consolidation of soil. By analyzing the simulation results, we have obtained. (1) dissipation of pore water pressure in the process of soil self-gravity consolidation. The initial excess pore water pressure increases with the increase of density, and the dissipation rate of excess pore water pressure increases with the increase of permeability coefficient. The excess pore water pressure dissipation has gone through the stages of slow acceleration dissipation, fast dissipation and slow down dissipation. The relationship between the excess pore water pressure dissipation and time during consolidation can be described by formula 3-2). (2) the law of increasing soil pressure in the process of soil self-gravity consolidation. The soil pressure increases with the increase of density, and the growth rate of soil pressure increases with the increase of permeability coefficient. The increasing law of earth pressure with consolidation time includes the stages of slow acceleration, rapid growth and slow deceleration, and its dissipating law can be described by formula 4-3). Development law of consolidation settlement and deformation in the process of self-gravity consolidation of soil. The consolidation settlement increases with the increase of density, and the growth rate of consolidation settlement increases with the increase of permeability coefficient. With the increase of consolidation time, the consolidation settlement can be divided into two stages: slow acceleration settlement, rapid settlement and slow down settlement, and the development law of consolidation settlement with time can be described by formula 5-3).
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU43

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