一种桩网路堤荷载传递机制的简化分析方法

A simplified method to analyze load transfer mechanisms of geosynthetic-reinforced and pile-supported embankment

桩网路堤已经被认为是解决软土地基上修建路堤沉降以及不均匀沉降过大的有效途径。针对正方形布桩的桩网路堤的正方形布桩型式,提出一种桩网路堤荷载传递的简化分析方法。该方法考虑了土拱效应、地基支承作用、土工格栅效应以及桩土间力的传递,将土工格栅的变形用抛物线方程表示,最终推导得到关于地基表层荷载的一元三次方程。通过求解此方程得到地基表层荷载,进而求得地基表层最大沉降、土工格栅拉力和变形方程。最后通过现场试验验证并与主流计算方法进行对比分析,表明本文提出的方法推导概念和计算过程简便,计算结果可靠,可用于桩网路堤的设计计算。

Geosynthetic-reinforced and pile-supported embankment,has been considered as an effective and economic solution to reduce the total and differential settlements of the embankment constructed on soft soil. In this paper,a simplified method for analysis of an embankment on soft soil and supported by a rectangular grid of piles and geosynthetic is proposed. In this method,the soil arching effect is analyzed by arching effect in granular material initially proposed by Low B.K. et al.,and subsoil resistance,geosynthetic effect and especially load transmission of pile and soil are taken into consideration. Quadratic parabolic equation is employed to described the deformation of the geosynthetic. Ultimately the expression for subsoil resistance has been deduced,and then the tension and the deformation expression of geosynthetic can be worked out. Through comparative analysis with field test and other current design methods, it is found that the proposed method is conceptually and mathematically simple,and the results agree well with field test data and that of several current design methods.