基于应力叠加的群桩效应系数的研究

根据附加应力叠加原理，逐步推导得到不同布桩形式的群桩效应系数计算公式。计算表明，当桩数、桩长、桩径相同时，单位承台面积上的群桩效应系数，呈梅花形布桩的最大，呈矩形布桩的次之，呈正方形布桩的最小。因此，呈梅花形布桩群桩是较好的选择。这为苏通长江公路大桥主桥超长大直径群桩基础选择呈梅花形布桩提供理论依据。

Research on Effect Coefficient of Piles Group Based on Stress Superposition

The formula for effect coefficient of piles group were solved gradually under different shape of laying-out piles according to principle of additional stress superposition.It proved that,when sum of piles,length of piles and diameter of piles were equal,effect coefficient of piles group per m2 was at the maximum with quincunx laying-out piles,next rectangle and minimum square,the quincunx laying-out piles groups was a better choice than the others laying-out piles group in many cases.The theory could be designed for extra-long and large diameter piles group under south bridge tower of leading bridge of Sutong Yangtse River Highway Bridges.