摘要
针对螺纹桩承载机理的研究不足问题,以螺纹桩单桩加载模型试验及数值模型结果为基础,分析螺纹桩破坏模式变化规律,提出不同破坏模式下螺纹桩极限承载力的归一化计算方法,研究结论如下:在圆柱形剪切破坏模式和单独承载破坏模式之间存在一种过渡性破坏模式——连拱圆柱形剪切破坏模式,该模式兼具两种典型破坏模式的特点,破坏面的外轮廓仍近似呈圆柱形,但各级螺牙间的破坏面又形成一定的拱,并随着螺距的增加有向单独承载破坏模式发展的趋势;当螺距接近临界螺距时,螺纹桩一般呈连拱圆柱形剪切破坏模式,螺牙下土体塑性区发展可分为四个阶段,即初始阶段、扩张阶段、初贯通阶段、拱形极限阶段;通过模型试验结果讨论了连拱圆柱形剪切破坏下螺纹桩极限承载力计算方法的合理性,为螺纹桩设计工作提供了一定理论参考。
Aiming at the problem of insufficient research on the bearing mechanism of screw piles,based on the results of single pile loading model test and numerical model test,different failure modes of screw piles are analyzed,and a normalized calculation method for the ultimate bearing capacity of screw piles under different failure modes is proposed.The research conclusions are as follows.There is a transitional failure mode between the cylindrical shear failure mode and the individual bearing failure mode,namely,the multi-arch cylindrical shear failure mode,which has the characteristics of the two typical failure modes.The external contour of the failure surface is still approximately cylindrical,but the failure surface between the adjacent screw teeth will form a certain arch,and tends to develop to the individual bearing failure mode with the increase of the screw pitch.When the screw pitch is close to the critical screw pitch,the screw pile generally presents multi-arch cylindrical shear failure mode,and the development of plastic zone under the screw can be divided into four stages:initial stage,expansion stage,initial penetration stage and arch-shape limit stage.Based on the model test results,the rationality of the calculation method for the ultimate bearing capacity of screw pile under multi-arch cylindrical shear failure is discussed,which provides a theoretical reference for the design of screw pile.
作者
罗丽娟
马甲宽
王博宇
苗壮
毛君
Luo Lijuan;Ma Jiakuan;Wang Boyu;Miao Zhuang;Mao Jun(School of Civil Engineering,Chang'an University,Xi'an 710064,China;School of Civil and Ocean Engineering,Jiangsu Ocean University,Lianyungang 222005,China;Xi'an Railway Survey and Design Institute Co.Ltd,Xi'an 710054,China;CCTEG Ecological Environment Technology Co.Ltd,Xi'an 710054,China)
出处
《建筑科学》
北大核心
2025年第5期105-113,共9页
Building Science
基金
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资助项目(300102289201)。
关键词
螺纹桩
圆柱形剪切破坏
单独承载破坏
连拱圆柱形剪切破坏
极限承载力
screw pile
cylindrical shear failure
individual bearing failure
multi-arch cylindrical shear failure
ultimate bearing capacity
