Effects of tunneling on vertical bearing behaviors of adjacent single pile

Based on load transfer method and Winkler model,an elastoplastic solution of tunnel-pile interaction is given by the two-stage method to analyze the vertical behavior of adjacent single pile due to tunneling.The long-term and the short-term vertical behaviors of adjacent single pile are analyzed.The results are compared with that obtained from some existing centrifuge model tests,and then a good agreement is observed.The influences of the distance between tunnel center line and the ground surface,the distance between tunnel center line and the pile axis,ground loss,pile length,pile diameter and pile strength on the vertical behavior of adjacent single pile due to tunneling are analyzed;and the influence regularity is presented.The results show that:(a) the distance between tunnel center line and the ground surface increases,the pile settlement and pile axis force firstly increases and then gradually decreases;(b) the distance between tunnel center line and the pile axis increases,the pile settlement decreases gradually,the pile axis force increases to a certain value and then gradually decreases;(c) with the increase of ground loss,the pile settlement is continuously increasing,the pile axis force gradually increases to a stable value.