Analysis on the Vibration Influence on Upper Buildings Induced by Cutting of Pile Group by Extra-large-diameter Shield in Dense Urban Areas
Construction of a shield tunnel in a central urban area will inevitably encounter the pile foundations of existing buildings or structures,but direct cutting of the pile foundation will impose enormous risks.In order to fur-ther reveal the internal mechanism of cutting of pile foundation by a shield,the case of the Haizhu Bay Tunnel cutting through the foundation of CNNC Business Building is used as an example in this study.The field measured vibration data is used to analyze the pattern of the vibration response of CNNC Business Building induced by the shield grinding the pile foundation,and to investigate the tilt of the building caused by the shield grinding the pile foundation.As the study results indicate:The building mainly experiences vertical vibration when the shield grinds the pile founda-tion.Inside the building,the vibration is quickly attenuated as its propagation distance increases,so the vibration in-duced by shield construction impacts only a small area.The area in 2/3D(D is the shield diameter)with the tunnel center line being the axis is the key impact area.As indicated by the monitoring results,the vibration catastrophe am-plitude of the first floor,which is closest to the shield tunnel,is over 2 times the vibration catastrophe amplitude of the second floor.According to the study,the vibration amplitude will indicate the direction of tilt of the building,so the direction of tilt of the building can be analyzed by monitoring its vibration variation.
Extra-large-diameter shieldShield constructionCutting of pile foundationBuilding vibrationField monitoring
NETL
NSTL
万方数据
