• 船舶海洋与建筑工程 •

### 基于统一强度理论的螺纹桩承载力计算方法

1. a.长安大学 建筑工程学院,西安 710064
b.长安大学 地下结构与工程研究所,西安 710064
• 收稿日期:2021-03-10 出版日期:2022-06-28 发布日期:2022-07-04
• 通讯作者: 罗丽娟 E-mail:luojuan@chd.edu.cn
• 作者简介:马甲宽(1993-),男,河南省濮阳市人,博士生,主要从事桩基础工程方面研究.
• 基金资助:
国家自然科学基金(42077248);国家自然科学基金(41877285);中央高校基本科研业务费(300102289201)

### Calculation Method of Bearing Capacity of Screw Pile Based on Unified Strength Theory

MA Jiakuana, LUO Lijuana,b(), REN Xianga, SHI Hanga, YIN Yimoa

1. a. School of Civil Engineering, Chang’an University, Xi’an 710064, China
b. Institute of Underground Structure and Engineering, Chang’an University, Xi’an 710064, China
• Received:2021-03-10 Online:2022-06-28 Published:2022-07-04
• Contact: LUO Lijuan E-mail:luojuan@chd.edu.cn

Abstract:

Based on the unified strength theory and the Terzaghi limit equilibrium theory, the ultimate bearing capacity of screw pile has been deduced. The method to determine the critical pitch and calculate the ultimate bearing capacity of the screw pile in two failure modes including the independent bearing failure mode and the cylinder shear failure mode has been proposed. The influence of the unified strength theoretical parameter b and the key parameters of concrete screw pile on the ultimate bearing capacity has been analyzed. The results show that the ultimate bearing capacity of the screw pile is 1.5—2 times that of the round pile with the same outer diameter. The ultimate bearing capacity of the screw teeth is mainly determined by the cohesion, the internal friction angle, and the buried depth of the soil. As b increases from 0 to 1, the theoretical value of the ultimate bearing capacity of the screw pile increases by nearly 48%. As the influence of the medium principal stress on the soil strength is considered, the theoretical calculation results of the bearing capacity of the concrete screw pile will be more accurate. Of the parameters of the concrete screw pile, the screw height bh has the greatest influence on the ultimate bearing capacity, while the screw thickness t has little influence on the bearing capacity. When designing threaded pile, the height of screw can be increased to some extent to improve the ultimate bearing capacity of the screw pile.