双层土中单桩负摩阻力分布规律分析

文中依托传统的桩荷载传递函数法,建立单桩在双层土体中的负摩阻力传递力学模型。该模型考虑了土体的分层特性,假设土层沉降是一维且呈双折线分布,传递函数是线弹性全塑性关系,桩尖处所提供的反力呈线形变化。同时考虑桩侧土部分进入塑性变形的情况,在此基础上,对土体塑性深度发展状况及桩身中性点位置开展研究,该模型既适用于端承桩,又适用于摩擦桩。工程算例表明该模型符合实际情况。

Theoretical Analysis on Negative Friction Distribution of Single Pile in Double Layer Soil

Based on the traditional method of pile load transfer function,a mechanical model for calculating the negative friction resistance of a single pile in double-layered soil is presented.The model takes into account the layered characteristics of the soil.It is assumed that the settlement of the soil layer is one-dimensional and distributed as a double broken line,the transfer function is linear elastic and full plastic relationship,and the reaction force provided by the pile tip is linear.The plastic deformation and the development of plastic depth are also considered.The position of the neutral point is also discussed.The model is applicable to both end bearing pile and friction pile.An engineering example shows that the model presented in this paper is in good agreement with the actual situation.