摘要
对印尼苏拉马都跨海大桥9根超长钻孔灌注桩采用自平衡法进行了静载荷试验。测试得到了桩端压浆前后的桩基承载力、桩端阻力及桩侧摩阻力。根据压浆前后的试验数据进行分析,压浆后桩极限承载力提高幅度为10.32%~170%,桩端阻力提高幅度为8.46%~207.6%,侧摩阻力提高幅度为8.32%~120%,整桩承载特性得到明显改善。桩端压浆并不是单独作用于桩端,而是改善了整个桩土体系,使得侧摩阻力也得到大幅增长。压浆后桩端阻力所占桩承载力的比值有所增加,试桩由压浆前的摩擦桩,向端承摩擦桩过渡。另外,压浆量也存在一个合理的数值,需要根据实际地质条件进行压浆设计。
Static load tests are carried out with Osterberg method on nine super-long bored piles formed in Suramadu Bridge.Bearing capacity,base resistance and friction resistance are obtained before and after base grouting.Based on the test results,the ultimate bearing capacity of pile is increased for 10.32%~170%,that of pile base is increased for 8.46%~207.6%,and the frictional resistance is increased for 8.32%~120%,therefore pile bearing behavior is improved.Not only base resistances are improved after grouting,but also frictional resistances are improved by bettering the characteristics of soils and interfaces between piles and soils.After grouting,pile base resistance ratio of pile bearing capacity increased,and the friction pile changed into end-bearing friction pile.In addition,the grouting quantity has a reasonable value,the grouting design needs to be carried out according to practical geologic conditions.
出处
《公路》
北大核心
2011年第2期217-222,共6页
Highway
基金
国家自然科学基金项目
项目编号50908048
江苏省自然科学基金资助项目
项目编号BK2008315
关键词
钻孔灌注桩
承载性能
自平衡测试法
桩端后压浆
摩阻力
端阻力
bored piles
bearing capacity
Osterberg method
pile-base post-grouting
frictional resistance
base resistance
