摘要
通过对青藏高原风火山地区的桥梁钻孔灌注桩进行现场静载试验,研究了厚层地下冰地区高温不稳定冻土地段桥梁钻孔灌注桩的基桩承载力和变形特性,结果表明:厚层地下冰地区冻土如果受到扰动,其恢复过程非常缓慢;钻孔灌注桩的桩端阻力对整个桩基的承载力贡献较小,基桩周围土体的剪切变形大部分为塑性变形,沉降特性呈现出较为典型的摩擦桩特征;基桩轴力的荷载传递特性和桩侧阻力的发挥与桩顶所加荷载大小、桩周冻土的性质以及地温密切相关.
By virtue of the in-situ experiment carried out in Fenghuoshan region, a thick ground ice and warm permafrost region, of the Tibetan Plateau, the bearing characteristics of a large diameter cast-in-place bored pile and the shearing deformation of frozen soil around a large diameter cast-inplace bored pile are studied. The in-situ experimental results indicated that the frozen soil in thick ground ice region was difficult to refreeze once it had been disturbed due to human activity and the globe climate changes. Frozen soil around the pile mostly presented plastic deformation. Besides, the load-settlement of cast-in-place bored pile was characterized by the features of typical friction pile. The pile tip resistance of a large diameter cast-in-place bored pile had less loading sharing ratio. Pile shaft force and pile side resistance had something closed to do with pile top loading, characteristics of frozen soil around the pile and ground temperature around the pile.
出处
《冰川冻土》
CSCD
北大核心
2008年第3期482-487,共6页
Journal of Glaciology and Geocryology
基金
中国科学院“西部之光”人才培养计划项目
国家自然科学基金重点项目(50534040)
国家重点基础研究发展计划(973计划)项目(2002CB412704)资助
关键词
钻孔灌注桩
多年冻土
桩侧阻力
基桩承载力
cast-in-place bored pile
permafrost
pile side resistance
pile bearing capacity
