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 and
the strain rate parameter
pile spacing
and pile length —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 and and the strain rate parameter
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
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