（1 宁波市机电工业研究设计院 315012;  2 宁波大学地基处理中心 315000）
【提要】 预制空心方桩兼备预制桩和预应力管桩的一些特性。简要介绍了空心方桩的技术参数特性，分析了空心方桩桩侧和桩端阻力特征，并通过实验室试验和大量工程实例论述了单桩承载力和变形特性，提出了空心方桩极限承载力的计算公式。结论认为，在饱和软土地区，空心方桩单桩的工作性状良好，可有效提高桩侧阻力，减小沉降，比预应力管桩的单桩承载力高出20%～40%左右。
【关键词】 空心方桩 单桩 承载性状 承载力 特性
Bearing Performance and Engineering Application of Steel Concrete Hollow Square Pile/Pan Qi 1,Zhuang Zuocheng1, Chen Zhong2, Kong Chao2, Zhu Jiping1 (1 Ningbo Research Design Institude of MechanicalElectrical Industry, Ningbo　315012, China; 2 Soil Improvement Center of Ningbo University, Ningbo　315000,China)
Abstract:Prefabricate hollow square pile is a kind of new pile, of which performance is between the solid square pile and prestressed pipe pile. The technical parameter characteristics of hollow square pile and the characteristics of pile side and pile end resistance are introduced. Single pile bearing capacity and distortion characteristics got from experiments in the laboratory and many engineering examples are discussed and the calculation formula of hollow square pile limit bearing capacity is provided. It shows that the hollow square pile performances well in saturable soft slay area. It can improve pile side resistance effectively and decrease the sink. The single pile bearing capacity of hollow square pile is about 20%～40% higher than that of the prestressed pipe pile.
Keywords:hollow square pile； single pile； bearing performance； bearing capacity； characteristic