SEISMIC RESPONSE OF SUBWAY STATION WITH LARGE SPAN AND Y SHAPED COLUMN

Along with the development of subway construction, a new type of structure with long span and Y shaped column comes up.It is different from the existing subway station structure, the space is tall and spacious, which shows a comfortable environment.In order to study the seismic performance of subway station structure with this new type, taking Xinhua Street station of the Beijing Metro Line 6 as engineering background, FLAC ^3Dwas used to build the soilunderground structure dynamic model of three-dimensional finite difference to simulate the response process under the Xinhua Street artificial seismic wave excitation.Emphasis is put on the analysis of the law of acceleration, displacement and strain of both Y shaped column and side wall of the station.The numerical results are also compared with the shaking table test.The results show that the numerical results are basically identical with the shaking table test, which reflects the similar structure response.The maximum acceleration of Y shaped column occurred at the position just a little down from the top of the column, not at the top.Strain changes suddenly at the bifurcation position of Y shaped column, where this position also has the largest response displacement relative to the bottom of column and with abrupt change, so this is the part to be reinforced in aseismic design.The acceleration and change of displacement of Y shaped column are both larger than side wall.The results above may provide reasonable reference and guidance to improve the seismic performance and seismic design for similar subway station structure.