考虑大气温度变化的冻土区桩基承载力预测  

Pile Bearing Capacity Prediction Considering Air Temperature Change in Cold Regions

作　　者：唐丽云[1] 杨更社[1] 叶万军[1] 

机构地区：[1]西安科技大学建筑与土木工程学院,西安710054

出　　处：《地下空间与工程学报》2015年第3期652-657,共6页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基资助项目金(41272340);陕西省重点科技创新团队计划(2014KCT-30);陕西省科技统筹创新工程(2011KTZ03-02-01)

摘　　要：大气温度变暖情况下,研究冻土桩基承载力变化规律,可为设计年限内预测工程结构物的工作状况提供科学依据。根据桩端入土深度及桩土相互作用原理分别对季节性冻土地区桩基和多年冻土地区桩基进行分类,并建立相应的桩土相互作用模型。以实际桩基工程为例,首先,建立大气温度与地温之间的关系,得出冻结期和融化期地面平均温度;然后,建立冻土区季节冻结及季节融化深度和地面平均温度与多年冻土厚度的关系,得出冻土区季节冻结及季节融化深度变化和多年冻土厚度变化;进一步综合季节冻土及多年冻土桩基工作状况的不同,结合已建立的考虑温度变化的桩土相互作用模型,基于现行规范的单桩承载计算公式并考虑不同的土性物理参数的基础上,最终建立大气温度变化与桩基承载力相关方程,预测桩基承载力变化状况。以上研究方法可运用于冻土区桩基承载力初步预测。The change of pile bearing capacity was studied with air temperature raising. Pile foundations in seasonal frozen and permafrost regions were categorized and corresponding pile-soil interaction models were built according to pile-soil interaction theory and pile tip buried depth. Based on actual pile foundation project,the average surface temperature during freezing and thawing periods were obtained by establishing the relationship between the air temperature and ground temperature; the relation formula of active-layer thickness and average surface temperature and permafrost thickness was set up to get the variation of active-layer thickness and permafrost thickness with time;Based on existing norms and considering different soil physical parameters,a correlation equation of air temperature and pile bearing capacity was ultimately established combined with the pile different working conditions in seasonal frozen soil and permafrost and the pile-soil interaction model with temperature which was applied to predict the variation of pile bearing capacity with air temperature. The above methods can be applied to predict similar pile bearing capacity in cold regions.

关 键 词：大气温度变化 冻土区 桩基承载力 桩土相互作用模型 

分 类 号：TU473[建筑科学—结构工程]