PCC桩Q-S曲线Bolztmann模型拟合及承载力计算  

Fitting of Q-S curves and bearing capacity calculation of PCC pile

作　　者：蒋建平[1] 高广运[2] 章杨松[3] 

机构地区：[1]上海海事大学海洋环境与工程学院,上海200135 [2]同济大学土木工程学院,上海200092 [3]南京理工大学土木工程系,江苏南京210094

出　　处：《煤炭学报》2009年第4期531-536,共6页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(50678128);上海市教委科研基金资助项目(05FZ03);上海市教委交通运输与规划重点学科基金资助项目(J50601)

摘　　要：基于3个场地共13根桩的现场试验资料，对现浇混凝土薄壁筒桩进行了桩顶荷载-桩顶沉降曲线的数学拟合和承载力计算．结果表明，和抛物线模型、指数模型相比，本文建议的玻耳兹曼模型是描述薄壁筒桩桩顶荷载-桩顶沉降曲线的较好模型，它对直线型、缓变型、陡变型曲线都能进行较好的拟合；用玻耳兹曼模型拟合13根薄壁筒桩的桩顶荷载-桩项沉降曲线的效果很好，相关系数都达到0．9806以上，平均0．9926；对桩顶沉降已超过30mm的8根桩，Q30计算值与实测值误差百分比的绝对值在0．1100％～8．4400％，平均值为2．8975％，对桩顶沉降未达到30mm的5根桩，利用拟合方程式可对桩顶荷载Q30进行预测．Based on field loading test pile data in three engineering sites, it had a fitting analysis on the pile top load versus settlement curves （Q -s curves） and had a bearing capacity calculation of thin-wall cast-in-situ tubular piles. The results show that, compared with exponential model and parabola model, Boltzmann model is a better model describing pile top load versus settlement curves of thin-wall cast-in-situ tubular piles. And the model is all appropriate to linear type Q - S curves, slow change type Q - s curves and quick change type Q - S curves ; the regression effect of Boltzmann model is very good, the correlativity coefficients of 13 single piles are over 0. 980 6, the average value is 0. 992 6 ; the error percent between Q30 calcution value and testing value for 8 piles whose pile top settlement were larger than 30 mm is 0. 110 0% - 8. 440 0%, average value is 2. 897 5%, and the Q30 can be forecasted with fitting equations for 5 pils whose pile top settlement don＇ t reach 30mm.

关 键 词：桩顶荷载-桩顶沉降曲线 薄壁筒桩 玻耳兹曼模型 

分 类 号：TU473[建筑科学—结构工程]