单排桩-承台-联系梁组合基础受力分析

摘要

In order to solve the design problem of single row piles in engineering,the single row piles,the pile cap and the connection beam are regarded as a whole to carry out stress analysis.First of all,"single row piles-pile cap-connection beam" integrated model is established to analyze the effects of connection beam stiffness,adjacent foundation stiffness and differential foundation settlement,and to find out the related influencing factors.Then,"single row piles-pile cap-connection beam" SAP2000 finite element model is established to reflect the combined stiffness between the pile and the connection beam through "pile-soil effect".The forced displacement load is applied to reflect the influence of differential foundation settlement,and the stress of connection beam can be read directly from the model.The case analysis shows that this method can fully demonstrate the interaction between and among the pile (pile-soil effect),the pile cap and the connection beam and the stress state of "single row piles-pile cap-connection beam" is truly reflected to make the design of the connection beam more reasonable and reliable.%为了解决工程中常见的单排桩设计问题,将单排桩、承台及联系梁视为整体进行受力分析,避免了传统设计方法过于保守或偏于不安全的弊端.首先,建立“单排桩-承台-联系梁”一体化模型,对影响组合基础受力的联系梁刚度、相邻基础刚度及基础不均匀沉降进行理论分析,找出相互影响关系.然后,建立“单排桩-承台-联系梁”SAP2000有限元模型,模型通过“桩-土效应”反映桩基和联系梁的组合刚度关系,并以强迫位移荷载的方式考虑基础不均匀沉降的影响,联系梁的受力可从模型中直接读取.实例分析表明,该方法可充分考虑桩基(桩-土效应)、承台及联系梁间的相互作用,真实地反映“单排桩-承台-联系梁”的受力状态,联系梁的设计截面更合理、可靠.