The process of dynamic pile driving may cause large displacement of existing pile foundation, which will affect the safety and stability of buildings. Based on the anisotropic K₀ consolidated clay constitutive model, the calculation method of radius of failure zone and plastic zone of the surrounding soil is derived. Theoretical calculation formula of soil stress and excess pore pressure caused by pile driving is established. On this basis, taking excess pore pressure as external load, the transfer mode of excess pore pressure to surrounding soil is proposed based on the principle of minimum energy. The influence of excess pore pressure on radial stress of surrounding soil is deduced in semi-infinite space. Taking a project in Tianjin as an example, the research results are analyzed. The results show that the present closed-form elastic-plastic solution matches the existing solution fairly well, and the decay speed of the excess pore pressure in the plastic zone is significantly larger. When the pile spacing is small, the displacement of surrounding pile due to piling will be large.