摘要
本文针对混凝土灌注桩护筒受力问题,对护筒在钻进阶段与拔出阶段分别进行护筒受力分析,建立护筒钻进和拔出阶段的受力模型。根据建立的受力模型以及受力计算研究,提出护筒主要受力的理论计算公式。结果表明护筒受到的最大环向应力为混凝土灌注桩浇筑完成后混凝土对护筒内壁的挤压力,最大扭矩为钻进过程中护筒受到的扭矩,最大轴向力为护筒拔出过程中受到的拉力。对现场实例进行分析,结果表明所选取的护筒满足施工要求,护筒不会发生失稳破坏。本文提出的模型对全护筒跟进施工过程中护筒的尺寸选取和节约护筒成本具有一定的参考价值。
In order to determine the stress of the casing of concrete cast-in-place pile,the stress analysis of casing in drilling stage and pulling stage is carried out respectively,and the stress model is established for each stage.According to the established model and force calculation,the theoretical formula of the main force of the casing is proposed.The results show that the maximum circumferential stress of the casing is the extrusion force of the concrete on the inner wall of the casing after the concreting is completed;the maximum torque is the torque of the casing during the drilling process,and the maximum axial force is the pulling force during the casing pulling process.The practice application shows that the selected casing meets the construction requirements,and the casing will not break.The model proposed in this paper could be referred to select casing for the pile hole boring with full hole casing.
作者
于洋
张志奇
邹连松
郭灿
Yu Yang;Zhang Zhiqi;Zou Liansong;Guo Can(Road&Bridge International Co.,Ltd.,Chongqing 400000,China;China Communications Construction Company Rail Transit Branch,Beijing 102200,China;School of Resources and Safety Engineering,Central South University,Changsha 410083,China)
出处
《工程勘察》
2024年第9期25-28,43,共5页
Geotechnical Investigation & Surveying
关键词
混凝土灌注桩
护筒受力模型
稳定性分析
cast-in place concrete pile
force balance model of casing
stability analysis
