钢管埋深对钢管混凝土复合桩竖向承载特性影响研究  

Influence of Pipe Bury Depth on Vertical Bearing Characteristics of Steel Pipe Concrete Composite Pile

作　　者：冯忠居[1] 席称心 张其浪 戴国亮[3] 黄康[4] 甄东晓 王富春[1] 韩秋石 苏航州 

机构地区：[1]长安大学公路学院,西安市710064 [2]广东省南粤交通投资建设有限公司,广州市510000 [3]东南大学土木工程学院,南京市210096 [4]中交公路规划设计院有限公司,北京市100088 [5]中国建筑第七工程局有限公司技术中心,郑州市450000 [6]中国电建西北勘测设计研究院有限公司,西安市710000

出　　处：《公路》2018年第1期70-75,共6页Highway

摘　　要：结合广中江高速公路跨江桥梁钢管混凝土复合桩工程实际,采用数值仿真方法,对滨江大桥X3-15桩基础竖向承载特性进行数值仿真计算,并与现场试验成果进行对比分析,验证了有限元模型及参数的可靠性。在此基础上,深入研究了不同钢管埋深下钢管混凝土复合桩竖向承载特性的变化规律,计算结果表明,增大钢管埋深能有效提高钢管混凝土复合桩竖向极限承载力,钢管埋深在12m范围内增加时,桩基竖向极限承载力增加较快,钢管埋深每增加4m,桩基竖向承载力增幅2.0% ~2.2% ;钢管埋深超过12m后继续增加钢管埋深,桩基竖向极限承载力增加幅度较小,钢管埋深每增加4m,桩基竖向承载力增幅1.3% ~1.4% ;钢管混凝土复合桩竖向极限承载力由钢管段侧摩阻力、钢管段以下钢筋混凝土段侧摩阻力、钢管端部变截面处端阻力和桩端阻力组成;随着刚管埋深增大,钢管混凝土复合桩总侧阻力逐渐增大,总端阻力则均有所减小,钢管埋深由4 m增加至24 m时,桩基总侧阻力增大了6 382.8kN,增幅9.3% ,桩基总端阻力减小了6 382.8kN,减幅29.8% 。Based on the steel pipe concrete composite pile engineering for the river-crossing bridges on the Guangzhon-Zhongshan-Jiangmen Expressway, the vertical bearing characteristics of X3-15 pile foundation of Binjiang Bridge is calculated by numerical simulation, and the result is compared with the result of self-balancing test, and the reliability of the finite element model and parameters are verified. Based on above, the variation rules of steel pipe concrete composite pile vertical bearing characteristics are studied in depth under different steel pipe bury depth. The results show that： increase the steel pipe bury depth can effectively improve the vertical ultimate bearing capacity of the steel pipe concrete composite pile, the vertical ultimate bearing capacity can increase rapidly when the steel pipe bury depth is increased in the range of 12 m below the surface, and when the bury depth increase by 4 m, the vertical bearing capacity can grow by 2.0 % ~ 2.2% ; but the vertical ultimate bearing capacity increases slowly when the steel pipe bury depth is more than 12 m, and with a minor increase of 1.3%~1.4% every 4 m of steel pipe bury depth; the vertical ultimate bearing capacity is composed of steel pipe friction, reinforced concrete friction, the tip resistance of steel pipe and the tip resistance of pile; the friction of the steel pipe concrete composite pile is increased by 6 382.8 kN at a growth ratio of 9.3 %, and the tip resistance of the steel pipe concrete composite pile is decreased by 6 382. 8 kN at a decrease ratio of 29.8% when the steel pipe depth is increased from 4 m to 24 m.

关 键 词：钢管混凝土复合桩 自平衡试验 数值仿真 竖向承载力 对比分析 研究 

分 类 号：U443.15[建筑科学—桥梁与隧道工程]