疏桩复合地基不均匀沉降原因分析及处理

Non-uniform Settlement Analysis and Reinforcement of Settlement-controlled Composite Pile Foundation

沿海深厚软土地区常面临地基不均匀沉降问题,当天然地基承载力满足承载要求或相差不大的情况下,综合考虑工期等因素选用疏桩复合地基是比较合理的,一般选用4~6倍桩距(D=4d^6d)的疏桩布置,摩擦桩与桩间土共同承担上部荷载构成复合地基。工程实践过程中受气候、环境、施工工艺等多种因素影响,复合地基所设想的桩-土协同工作较难实现,刚性桩与桩间土的沉降差易出现不均匀沉降问题。本文通过对工程实例的分析,初步阐述了该工程复合地基出现不均匀沉降的原因及后续处理措施,不断完善疏桩复合地基处理方法。

Non-uniform settlement of the foundation is often faced in deep soft soil along the coast. When the natural foundation bearing capacity meets the bearing requirements or there is not much difference, it is reasonable to consider the construction period and other factors to select sparse pile composite foundation. Generally, 4~6 times the pile spacing(D=4 d^6 d) is used for the sparse pile layout.The friction pile and the soil between the piles jointly bear the upper load to form a composite foundation. Affected by many factors such as climate, environment, and construction technology during engineering practice, the pile-soil cooperative work envisaged for composite foundations is difficult to achieve, and the settlement difference between rigid piles and soil between piles is prone to uneven settlement problems. Through analysis of engineering examples, this paper preliminarily elaborates the reasons for the uneven settlement of the composite foundation of the project and the follow-up treatment measures, and continuously improves the treatment method of sparse pile composite foundation.