摘要
太湖软土地层广泛分布有较厚的淤泥质粉质黏土层,该淤泥质软弱夹层含水率高、压缩性大,呈流塑态,工程性质极差。以毗邻太湖苏州文博中心桩基建设项目为依托,基于现场试桩试验和CPTU测试p–y曲线法,研究了太湖软土地层超长灌注桩的水平承载特性,明确了淤泥质软弱夹层厚度对单桩水平承载性状的影响规律。案例分析表明：基于CPTU测试单桩水平承载数值计算结果与试桩试验结果吻合较好,桩基承载性状匹配一致;受淤泥质软弱夹层的影响,太湖软土地层水平受荷桩荷载传递深度较深,桩顶水平荷载的影响深度超过20 m;淤泥质软弱夹层的厚度既改变了桩身截面最大弯矩值又影响了截面最大弯矩及弯矩零点的发生位置;在软弱夹层普遍分布厚度0.5-6.0 m范围内,随夹层厚度的增加,软弱夹层变化带来的桩顶水平变位及桩身弯矩递增效应逐渐降低。以上研究成果可为软土地层桩基水平承载设计实践提供技术支撑。
The muddy silty clay is rich in organic matter and widely distributed in Taihu soft soil foundation. It has a large water content and compressibility and is in a state of flow plasticity. All of these make it have bad engineering properties. Based on a pile foundation project which is adjacent to Taihu Lake, through the field pile tests and the p-y curve method of CPTU tests, the lateral bearing characteristics of super-long bored piles in Taihu soft soils and the response laws to the thickness change of muddy soft interlayer are studied. The case study show that the results of numerical calculation from CPTU data agree well with those of the field pile tests, and the load transfer depth is more than 20 m of laterally loaded piles in Taihu soft soils as a result of the influence of muddy soft interlayer. The values and positions of the maximum bending moment and zero point are changed in view of different muddy soft interlayer thicknesses. Within the scope of 0.5-6.0 m, the increment of pile top displacements and the bending moments due to the increasing interlayer thickness decrease. The above research achievements may provide technical supports for the design of laterally loaded piles in Taihu soft soils.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2018年第2期378-383,共6页
Chinese Journal of Geotechnical Engineering
基金
国家重点研发计划项目(2016YFC0800201)
江苏省建设系统科技项目(2014ZD66)
中央高校基本科研业务费专项
江苏省普通高校研究生科研创新计划项目(KYLX16_0244)
