摘要
提出了新型的桩 桶基础的设计概念,并进行了上拔荷载作用下的数值模拟试验。桩 桶基础是桩和桶的结合,结合了桩基础、桶基础在海洋工程中体现的各自优势。通过颗粒流理论和PFC2D程序,应用细观力学的方法对上拔荷载作用下的桩 桶基础进行了模拟试验,研究了桩 桶基础在客观存在上拔荷载过程中土颗粒的分布及变化、土颗粒的位移与变化,基础的上拔位移与时步关系,土体受上拔荷载影响区域的范围及其变化。根据土颗粒的分布、颗粒的结构、颗粒的位移及其变化,基础位移与时步曲线的凸、凹变化表明了土体的稳定与破坏,判定了基础上拔时的土中滑动破坏面为锥体,综合确定了极限上拔承载力,对基础受荷过程中土颗粒细观结构变化,针对颗粒流仿真试样的细观力学特征与宏观力学响应进行了初步研究并揭示了一些规律。
Design of new type of pile-bucket foundation was put forward and pile-bucket foundation on uplift loading was tested with numerical simulation method.The pile-bucket foundation was the combination of advantage of pile foundation with that of bucket foundation in ocean engineering.PFC^(2D)(Particle Flow Code in 2 Dimensions)simulated numerically the character of meso-mechanics on sand particles,studied distribution and velocity of sand particles and uplifting displacements of pile-bucket,affected the zone of particle was from large to small,arrangements of particles were changed from before to after uplift loading,tapered affected zone of particle was formed;displacement-time were simulated numerically on uplift loading,convey and concave curves of displacement-time showed stability or failure of sand,plane of rupture and ultimate uplift bearing capacity was defined.Changes of soil particle meso-structure and displacement of piles-bucket of Particle Flow Code numerical simulation are initial study on meso-mechanics character and macro-mechanics response.
出处
《水道港口》
2004年第2期69-74,共6页
Journal of Waterway and Harbor
基金
国家自然科学基金项目(59968001
50178054)
上海教育委员会科学技术项目(03IK03)
关键词
桩-桶基础
上拔荷载
细观力学
颗粒流理论
数值模拟
pile-bucket foundation
uplift loading
meso-mechanics
particle flow code
numerical simulation
