人工挖孔桩桩端阻力经验公式的变异性分析  

Variability Analysis of Empirical Formula of Resistance to Pile End on a Manually Dug Hole Bottom

作　　者：王利群[1] 赵文[1] 李艺[1] 

机构地区：[1]东北大学资源与土木工程学院,辽宁沈阳110004

出　　处：《东北大学学报（自然科学版）》2010年第4期593-596,共4页Journal of Northeastern University(Natural Science)

基　　金：国家自然科学基金资助项目(50508008)

摘　　要：指出经验公式确定挖孔桩桩端阻力标准值的变异性是由经验公式本身的不确定性、桩端直径的不确定性和动探击数的不确定性组成.根据随机场理论和协方差传播律,推导出了考虑动探击数自相关性的经验公式变异性的计算公式和经验公式本身变异性的计算公式,给出了桩端直径的统计参数.通过实例进一步证明了对于砂类土和碎石类土地基,利用重型动力触探数据计算相关距离是合适的,而且重型动力触探击数之间是相关的.It was found that the standard value of the resistance to pile end on a manually dug hole bottom,which was calculated by an empirical formula,is variable,and the variability consists of the uncertainties of the formula itself,pile end diameter and number of heavy-duty DPTs.The calculating formulae were derived according to random field theory and variance propagation law for the variability of the empirical formula itself and the empirical formula considering the self-correlation of the number of DPTs,with the statistical parameter of pile end diameter given.A numerical example showed that the heavy-duty DPT data are suitable to the calculation of correlated distance for the foundations of sand soil and gravelly soil,and each of the number of DPTs correlates to the other one.

关 键 词：人工挖孔桩 承载力 相关距离 重型动力触探试验 空间变异性 

分 类 号：TU473.1[建筑科学—结构工程]