Study On Seismic Dynamic Response Of Xudizi Tunnel In Ya'Lu Expressway

As a special structure of tunnel constructed at high seismic intensity location, it is necessary to be studied on double-arch tunnel in seismic response and the corresponding measures of aseismic and shock absorption. This paper is research on seismic dynamic response of double-arch tunnel, and numerical modeling is applied to analyzing seismic dynamic response rules of portal of double-arc tunnel. This paper's contents are summarized as following:1. The effects of many factors on seismic dynamic response of double-arch tunnel, such as depth of burial, parameters of surrounding rock, lining stiffness, are numerical modeling, and rules of variation in corresponding parameters are analyzed.2. The effects of shock absorptions are analyzed by way of changing depth of grouting and material properties of shock absorption layer, and the influences of variations of depth of grouting and material properties are summarized.3. The portal of Xudianzi tunnel, which is double-arch ,via neighborhood tunnel and gradually separated, are numerical modeling, and the rules of variation of displacement peak and internal force peak in transition sections are analyzed. Meanwhile, the seismic dynamic responses of the middle column are studied in particular.By the above study, the following conclusions are reached :1. The lining of the Xudianzi tunnel portal could meet the basic force requirements of the structure. And at the Ya'an port, the changing section of the sidewall feet of the double-arch tunnel, endures biggish force, so it is needed to be strengthened partially.2. The mid-wall of the Xudianzi tunnel portal can't meet the basic force requirements of the structure. Steel is needed to be added to strengthen the structure.