刚柔性长短桩复合地基性状分析

Engineering characteristics of composite foundation with rigid-flexible and long-short piles

对刚柔性长短桩复合地基的工程性状进行了分析研究。利用有限元方法对不同的垫层模量、垫层厚度、短桩模量及长桩长度对长短桩复合地基的总沉降、长短桩应力比和长短桩桩身应力所产生的影响及规律进行了分析。结果表明,优化材料参数可以较好地改善长短桩复合地基的受力性状,使基础受力更合理。另外,长桩的存在可有效减小地基沉降值。结合对温州某小区该类型地基埋设压力盒的现场监测,分析了实际工程中刚柔性长短桩复合地基的应力比和土压力的发展规律。其结果可为该类型复合地基的设计和应用提供参考。

The engineering characteristics of composite foundation with rigid-flexible and long-short piles are studied. By using the finite element method, the effects of cushion modulus, cushion thickness, short pile modulus, and long pile length on the total settlement of composite foundation, the stress ratio of long-short pile, and the axial stress of long-short pile are discussed respectively. The results show that the engineering characteristics of composite foundation can become more reasonable by optimizing material parameters; and long pile can effectively reduce settlement of composite foundation. Based on the in-situ measurement of pressures in soil and piles of a practical engineering in Wenzhou City, stress ratio of pile to soil and pressures in the process of construction are analyzed. Some conclusions are provided as references for future design and application of this kind of composite foundation.