长短桩、变径桩桩间相互作用系数数值研究

采用三维数值方法,建立长短桩、变径桩双桩模型,通过大量的数值计算,分析桩顶荷载水平、桩距径比、不同桩长、桩端土模量比及不同桩径对相互作用系数的影响。分析表明,在线弹性变形阶段,桩-桩相互作用系数近似为恒定值,与桩顶荷载水平无关,进入塑性变形之后,则逐渐减小直至极限状态时趋于0;长短桩桩长比及桩端土模量比对短桩-长桩相互作用系数影响大,而对长桩-短桩相互作用系数影响小;变径桩相互作用系数仅与受荷桩桩径有关;并提出了针对长短桩、变径桩的简化计算公式,为实际工程提供参考。

Numerical analysis on pile-pile interaction factors between two dissimilar piles

Using 3D numerical simulation method,pile-pile models of long-short piles and piles with dissimilar diameters were built. Then the influences of various parameters on interaction factors were studied by numerical simulation of the pile-pile models,including pile top load,pile spacing,dissimilar lengths,pile end soil modulus ratio and dissimilar diameters. The pile-pile interaction factor remained constant in linear elastic deformation of loading piles,but decreased gradually until close to 0 in plastic state. Pile lengths ratio and pile end soil modulus ratio had more influences on longshort piles＇ interaction factors than that on short-long piles; the interaction factors for piles with different diameters were only affected by the loading pile＇s diameter. Lastly,simplified formulas of interaction factors between two dissimilar piles were proposed,which are applicable in practical engineering.