| With the development of the economy, more and more airports in the expansionare confronted with the requirements of implementing subterranean crossing under theairport, complex ground terrain and geological conditions, large-scale high fillexisting and short airport construction period are the main characteristics of theseairports construction. When the tunnel running across these high fills, it not onlyneeds to satisfy the parameters requirements of the tunnel structure itself,but also tomeet the strict environmental control and safe control requirements of the airport area.It is no doubt that the design and construction of airport high fill area tunnel ischallenged, and the stability of the tunnel operation structure is higher requested.Based on the planning project of Jiangbei airport tunnel, a detailed study is madewhich aiming at the influence of the airplane load brings to tunnel operation. It mainlydoes the following aspects of work:First, introduced the introducing Jiangbei airport the general situation of theinter-city railway tunnel, summarized the airfield to build a tunnel in the presentsituation;Second, the basic finite element theory of geotechnical engineering andcommonly used constitutive model and yield criterion of geotechnical structure areintroduced in this paper;Third, research of the aircraft load at the role in the tunnel, and identified theaircraft load;Fourth, analyze the three dimension finite element model of tunnel structureacted under the plane load and dynamic response characteristics of the tunnelstructure acted on the plane load.Fifth, set up three dimension finite element model of tunnel structure withdifferent depth and different modes of transportation, analyze the tunnel buried depthinfluenced by the large-scale mobile plane load, and point out the depth of high filltunnel influenced by the large-scale mobile plane load.According to the several aspects of research above, the law of dynamic responseof the tunnel structure which acted on the plane load is concluded. it is graduallydecreasing down by the tunnel vault. the dynamic response law of single hole andline tunnel structure is basically accordant with the single hole two-lane tunnel structure. The depth of the high fill tunnel influenced by plane load is more than15m,therefore, it is suggested that tunnel buried depth should be more than25m, andadopting the single hole two lane tunnel profile form. |
