塌落触地振动对地铁管片结构的影响研究

Study on Influence of Impact Vibration on Subway Segments Structure

为研究建（构）筑物爆破拆除塌落触地振动对地铁管片结构的影响,结合武汉市精武片区爆破拆除工程,采用ANSYS有限元软件对周边地铁管片结构进行了模态分析和动力响应研究。模态分析的计算结果表明：地铁管片结构的前十阶主振频率在0.1-0.26 Hz之间,属于低频。说明管片结构对低频的触地振动比较敏感,低频成分高的触地振动更容易对其造成破坏。塌落触地振动作用下地铁管片结构的动力响应计算结果表明,行车道墙角处的质点振动速度峰值与实测值比较吻合,地铁结构顶板和侧帮位置处的最大主应力值比较接近,最大值为3.24 MPa,低于钢筋混凝土材料的拉伸极限。

The influence of subway segments structure under impact vibration induced by collapse of building in demolition blasting is studied based on demolition blasting of buildings in JingWu district in Wuhan city. Modal analysis and dynamic response of subway segments structure are researched by using finite element software ANSYS. The modal analysis of the subway shield tunnel segments shows that the first ten natural frequencies between 0.1- 0.26 Hz belong to low frequency, so the structure of subway tunnel is more sensitive to the low frequency vibration, and the impact vibration with low frequency can make damage to shield tunnel more easily. The dynamic response of subway segments structure under impact vibration shows that the peak value of vibration velocity on driveway comer is consistent with the measurement one. The maximum principle stress on the roof is close to the value on side parts. The peak value is 3.24 MPa which is less than the limit value of reinforced concrete.