通过ABAQUS有限元软件,建立四桩基础三维有限元数值模型,并开发VUMAT用户子程序实现软黏土应变软化本构关系,系统研究应变软化参数δrem和ξ95、应变率参数μ、桩间距S、桩长L等关键参数对四桩基础水平极限承载力的影响规律,重点揭示桩群相互作用的主导作用。参数分析表明,水平承载力系数随应变软化参数δrem、ξ95和应变率参数μ的增大而增大,且不同参数对承载力的影响程度存在显著差异。随着桩间距和桩长的增加,桩群相互作用减弱,导致承载力增幅减小,其破坏机制也会发生转变。最后,基于人工神经网络建立考虑多参数影响的四桩基础水平承载力预测模型。
Abstract
A three-dimensional finite element model of a four-pile foundation is established using ABAQUS software, and the strain softening constitutive relationship of soft clay is implemented through a VUMAT user subroutine. This study systematically investigates the influence of key parameters—such as the strain softening parameters δrem and ξ95, the strain rate parameter μ, pile spacing S, and pile length L—on the horizontal ultimate bearing capacity of a four-pile foundation, with a focus on revealing the dominant role of pile group interaction. Parametric analysis reveals that the horizontal bearing capacity factor increases with the strain softening parameters δrem and ξ95 and the strain rate parameter μ, with notable differences in the degree of influence among these parameters. As the pile spacing and pile length increase, the pile group interaction weakens, resulting in a diminishing increase in the bearing capacity and a transition in failure mechanism. Finally, an artificial neural network-based prediction model for the horizontal bearing capacity of the four-pile foundation is established, incorporating the effects of multiple parameters.
关键词
风力机 /
黏土 /
应变率 /
桩基础 /
水平承载力 /
应变软化
Key words
wind turbines /
clay /
strain rate /
pile foundation /
horizontal bearing capacity /
strain softening
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基金
国家自然科学基金（52378357）; 教育部“春晖计划”合作科研项目（HZKY20220416）; 辽宁省教育厅高校基本科研项目（JYTMS20231608）; 沈阳市优秀中青年科技人才项目（RC230805）
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