摘要
通过模型试验研究竖直桩与倾斜角度为5°,8°,10°和15°倾斜桩的承载性能,分析倾斜对塑料套管现浇混凝土桩(以下简称TC桩)单桩承载力、桩顶沉降、桩身水平位移、桩身弯矩、桩身轴力及侧摩阻力和端阻比的影响。模型试验结果表明:(1)当TC桩倾斜度不大于8°时,对承载力和桩顶沉降影响不明显,对于倾斜10°,15°的桩,承载力明显降低;(2)倾斜桩桩身水平位移和弯矩主要发生于1/3桩长范围内,且均随着荷载和倾角的增加而增大;(3)竖直桩及各倾斜桩的侧摩阻力随深度的增加呈先增大后减小的趋势,随着倾角的增大桩极限侧摩阻力的平均值略有增大,侧摩阻分担比较大;(4)端阻力和端阻比基本随荷载的增加而增加,随倾角的增加而减小。采用Origin软件应用Sigmoidal函数拟合,得出模型桩极限承载力随桩体倾角的计算公式,并根据现场实测数据,给出现场应用时修正系数的取值范围。
The bearing behaviors of vertical pile and inclined piles with inclination angles of 5°,8°,10° and 15° are contrasted according to model test.Effects of inclination on the bearing capacity of single plastic tube cast-in-place concrete pile（TC pile for short）,pile-top settlement,pile shaft horizontal displacement,bending moment along pile shaft,skin friction and the ratio of tip resistance to load on pile top are analyzed.The model test results show that：（1） Effects of pile inclination on the bearing capacity and pile-top settlement are not apparent when the inclination angle of TC pile is less than 8°;but for the inclined piles with inclination angles of 10° and 15°,the reduction of bearing capacity of single pile is significant.（2） Horizontal displacement and bending moment of pile shaft mainly occur in the upper one third of pile length;and both go up with the increase of load and inclination angle.（3） Skin frictions of vertical pile and each inclined pile first increase and then decrease with the increase of pile depth;and the mean values of ultimate skin frictions increase slightly with the increase of inclination angle;and the bearing ratio of skin friction is large.（4） Tip resistance and the ratio of tip resistance to load on pile top go up with the increase of load and fall with the increase of inclination angle.The Origin software is applied to fit the curve between ultimate bearing capacity and inclination angle with Sigmoidal function.The formula is obtained to calculate the ultimate bearing capacity of inclined pile.Based on the field data,the range of correction factor is gained.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2011年第4期834-842,共9页
Chinese Journal of Rock Mechanics and Engineering
基金
浙江省交通运输厅科技计划项目(2007H03)
浙江省教育厅科研项目(Y200909862)
关键词
桩基工程
塑料套管现浇混凝土桩
承载性能
倾斜
模型试验
pile foundations
plastic tube cast-in-place concrete pile
bearing behavior
inclination
model test
