微型桩作为软土地基中的一种新型环保基础，具有承载力高、施工方便、占地面积小等优点，已逐渐在输电线路杆塔基础中得到应用。结合PLAXIS有限元程序数值分析方法，对不同桩长、不同桩身倾角、不同桩间距的微型桩基础的极限承载力进行了研究，给出了单桩的临界桩长、桩身最佳倾角、群桩效应系数的取值标准，为今后的工程设计与应用提供参考。

Abstract: As a new environmental protection in soft clay ground, micropile has the merit of higher bearing capacity, convenience and less occupancy for construction. It can be used in the foundation of transmission tower. By using the FEM program of PLAXIS and choosing appropriate material models, the ultimate bearing capacity of micropiles foundation are analyzed. Through theoretical analysis, the some factors influencing the bearing capacity of micropiles, such as length of pile, angle of incline pile, distance of piles and so on are studied. Key words: micropiles; transmission tower foundation; ultimate bearing capacity; PLAXIS finite element program.