Theoretical investigation on axial cyclic performance of monopile in sands using interface constitutive models  

作　　者：Pan Zhou Jingpei Li Kaoshan Dai Stefan Vogt Seyedmohsen Miraei 

机构地区：[1]Department of Geotechnical Engineering,Tongji University,Shanghai,200092,China [2]Department of Civil,Geo and Environmental Engineering,Technical University of Munich,Franz-Langinger-Str.10,München,81245,Germany [3]Department of Civil Engineering,Sichuan University,Chengdu,610065,China

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2024年第7期2645-2662,共18页岩石力学与岩土工程学报（英文版）

基　　金：the financial support provided by the National Natural Science Foundation of China(Grant No.42272310).

摘　　要：Cyclic loads generated by environmental factors,such as winds,waves,and trains,will likely lead to performance degradation in pile foundations,resulting in issues like permanent displacement accumulation and bearing capacity attenuation.This paper presents a semi-analytical solution for predicting the axial cyclic behavior of piles in sands.The solution relies on two enhanced nonlinear load-transfer models considering stress-strain hysteresis and cyclic degradation in the pile-soil interaction.Model parameters are calibrated through cyclic shear tests of the sand-steel interface and laboratory geotechnical testing of sands.A novel aspect involves the meticulous formulation of the shaft loadtransfer function using an interface constitutive model,which inherently inherits the interface model’s advantages,such as capturing hysteresis,hardening,degradation,and particle breakage.The semi-analytical solution is computed numerically using the matrix displacement method,and the calculated values are validated through model tests performed on non-displacement and displacement piles in sands.The results demonstrate that the predicted values show excellent agreement with the measured values for both the static and cyclic responses of piles in sands.The displacement pile response,including factors such as bearing capacity,mobilized shaft resistance,and convergence rate of permanent settlement,exhibit improvements compared to non-displacement piles attributed to the soil squeezing effect.This methodology presents an innovative analytical framework,allowing for integrating cyclic interface models into the theoretical investigation of pile responses.

关 键 词：PILES Cyclic degradation Load-transfer models Interface constitutive model Semi-analytical solution Model tests 

分 类 号：TU43[建筑科学—岩土工程]