【摘要】 研究了桩板结构复合地基设计理论和褥垫层调节沉降的作用机理,以已开通京津城际武清段2种不同CFG桩板复合地基处理形式为例,对比分析了加固区和下卧层不同位置的沉降-时间-荷载、应力-时间-荷载的变化特征。发现在桩板结构的桩顶设置褥垫层后使加固区内桩间土孔隙压力和沉降量增大,而下卧层的总沉降量和工后沉降量均较小。这表明了设置褥垫层后能有效地发挥复合地基桩间土的承载能力,提高了桩间土的固结度,达到减小其工后沉降的目的。更多还原

【Abstract】 The adjusting principle of settlement on the cushion and the design theory of pile-plank composite foundation were studied.Tow kinds of designs on pile-plank composite foundation were conducted on the Wuqing section of operated Beijing-Tianjin intercity railway.The change characters of settlement-time-load and stress-time-load were contrastively analyzed in the different depthes of reinforcement layer and subjacent bed.The result shows that when the cushion is placed bellow the plank of the foundation,the pore pressure and displacement of reinforcement layer at the level of pile are larger,while the total displacement and post-construction settlement of subjacent bed are relatively smaller.Which indicates that the bearing capacity and consolidation degree of soil among piles increase significantly by inserting the cushion,and the post-construction settlement is more restricted.更多还原