竖向承压螺旋桩基础极限承载力判定  

Estimation of ultimate load for a screw pile under the vertical pressure

作　　者：张亚军[1] 梁力[1] 董天文[2] 李明[1] 

机构地区：[1]东北大学资源与土木工程学院,辽宁沈阳110004 [2]辽宁省交通高等专科学校道桥系,辽宁沈阳110122

出　　处：《辽宁工程技术大学学报（自然科学版）》2009年第4期570-573,共4页Journal of Liaoning Technical University (Natural Science)

基　　金：辽宁省自然科学基金资助项目(2004308002)

摘　　要：通过对三种桩型的异型螺旋桩基础的静载荷试验,绘制了12条P-s曲线,分析了竖向静载荷作用下螺旋桩基础的桩土相互作用和承载性状特征,使用LogP-s方法判定了具有明确物理意义的承压螺旋桩基础极限荷载,讨论了地基土材料密实度、叶片距宽比(叶片间距与叶片净半径的比)对螺旋桩承载性状的影响。当叶片间土柱压密后,P-s曲线光滑,极限荷载增加,桩顶沉降减小;随叶片距宽比的增大,螺旋桩基础的极限荷载和桩顶位移均增大。The load displacement curve of screw pile usually shows the characteristic of multiple inflection points and discontinuation, therefore it is difficult to determine the ultimate load or its physical implications. The static loading tests on three types of screw pile foundations were conducted in this study. In the test, 12 P-s curves were obtained to analyse the pile-soil interaction and the loading characteristics under vertical static loads. In addition, the ultimate load of screw pile under vertical loads was estimated using Log P-s method. Also, the study investigated the load capacity characteristic from the aspect of the soil compactness and RDD （the ratio of laminas distance to the net radius of lamina）. After the soil between laminas was compacted, the P-s curves became smooth. With the increase of its ultimate load, the pile head settlements became slow. The ultimate load and settlement increased with RDD increase.

关 键 词：桩基础 螺旋桩 静载试验 极限承载力 

分 类 号：TU473.1[建筑科学—结构工程]