Responses of a short column-supported highrise tower to adjacent deep excavations in water-rich sandy strata and dynamic optimization of protection plans  

作　　者：Jun-Cheng LIU Yong TAN 

机构地区：[1]State Key Laboratory of Disaster Reduction in Civil Engineering,Department of Geotechnical Engineering,College of Civil Engineering,Tongji University,Shanghai 200092,China

出　　处：《Frontiers of Structural and Civil Engineering》2024年第11期1775-1793,共19页结构与土木工程前沿（英文版）

基　　金：National Natural Science Foundation of China(Grant No.42177179).

摘　　要：A highrise tower atop short columns in Nantong,China was threatened by excavation of a subway station nearby.Although an elaborate protection plan composed of isolation piles,artificial recharge and underpinning was executed throughout the excavations,the tower underwent unacceptable settlements and notable inclinations.In combination of field measurements and numerical simulations,this paper investigates the tower’s responses to the adjacent excavations,examines the effects of adopted protection plans and explores potential effective protection plans.First,the responses of the tower and the effectiveness of the three implemented measures were examined,and the contributory factors triggering intolerable tower deformations were identified;then,the effects of primary protection parameters were quantified,including the length,stiffness and layout of isolation piles,the water level surrounding recharge wells after recharging and the depth and location of wells,and the length of underpinning piles.It reveals that the underpinning plan had the best protection effect,followed by isolation piles and recharging wells.Construction timing of protection measures and termination manners of recharging are two critical factors in restraining tower deformations.Moreover,underpinning the tower with 36-m long steel pipe piles solely before implementation of adjacent excavations could be another optimal protection scheme.

关 键 词：highrise tower EXCAVATION piled-raft footing PROTECTION field performance numerical simulation 

分 类 号：TU473.1[建筑科学—结构工程]