碎石桩复合地基试验及固结分析

碎石桩复合地基在处理软弱地基土中得到相当广泛的应用。为了更好地掌握其规律性,本文针对某电厂碎石桩复合地基现场试验和桩身应力测试成果,进行了分析和总结,得出了饱和粘性土地基中桩土应力比与外荷载大小有关。其形状为上凸抛物线型,大小一般在3~6之间;静载荷试验下桩身应力分布特点与天然地基应力分布近似,影响深度为载荷板宽度的2~3倍。通过用有限元法模拟该复合地基固结性状,得知碎石桩不仅大大加快粘性土复合地基固结,而且减小了工后沉降的影响。 

Field tests and consolidation analysis of gravel pile composite foundation

The application of gravel pile composite foundation is extensive for reinforcing soft soil. In order to hold its regularity, this paper allows for the stress ratio of pile and its surrounding soil and the characteristic of pile body according to field tests and pile body stress testing of an electric factory. Stress ratio correlates with applied load, its form is a top-protruding parabola and its values are about 3~6. Through static test, the characteristic of pile stress is similar to that of natural foundation and the influencing depth is 2~3 times of loading plate. The consolidation of composite foundation is simulated by finite element method and its characteristic is that the gravel pile will not only greatly quicken the consolidation of composite-foundation but also lower the effect of post-construction settlement.