深处理可液化地层单桩水平承载性状研究

Study of horizontal bearing properties of single piles in deep liquefiable soils after treatment

依托江苏省宿迁市金鹰建设项目,利用自主研发的十字翼共振法处理深厚(7.9~15.7m)可液化粉土地层(夹粉砂),并联合采用标准贯入试验和孔压静力触探(CPTU)对场地处理效果进行了分析.重点通过CPTU原位技术对深处理液化地层单桩水平承载力提升测试进行了研究,构建了基于CPTU测试p-y曲线法的单桩水平承载数值计算模型,结合现场水平试桩结果,明确了液化地层处理后单桩水平承载力提升大小,获得了深部桩体的水平受力响应规律.结果表明:可液化地层处理后桩顶水平荷载的传递深度降低,桩体截面最大弯矩减小,试验场地单桩临界水平承载力较处理前提升了约30%.

Based on a Golden Eagle＇s project in Suqian,Jiangsu province,the resonant compaction method was used to deal with the liquefiable silt soil（7.9—15.7 mthickness）.Meanwhile,comparative in-situ tests including piezocone penetration test（CPTU）and standard penetration test（SPT）before and after improvement were conducted to assess the treatment effect.The testing study on horizontal bearing improvement of single piles was carried by CPTU technology,and the numerical calculation model was constructed based on the p-y curve method from CPTU parameters.Jointing test pile results,the enhancement of pile bearing capacity was determined.Moreover,the response properties of deep pile stress were obtained.The results show that the transmission depth of external pile top loadings decreases after improvement and the maximum bending moment reduces.The bearing capacity of single pile in test field increases by 30%.