Seismic Response Analysis Of Typical Urban Utility Tunnel System

Utility tunnel is a kind of municipal infrastructure which collected the pipelines in an intensive way instead of burying directly.It makes high use of the shallow space of the city and improves the ability of disaster prevention and reduction in city.It is considered to be one of the most effective way to solve the problems that arose in the process of urbanization.Currently,China is speeding up the popularization of urban utility tunnel.Many utility tunnels had been built or under-construction.And there is no lack of some in high seismology,so the anti-seismic work is in a desperate state.But,research at home on the anti-seismic of utility tunnel,which is an important lifeline facility,is premature.Thus,this thesis did a numerical simulation on the anti-seismic capacity of utility tunnel system.The researches of this thesis are as follows:1)Information of utility tunnel at home and abroad had been collected.Its characteristics and seismic damage characteristics had been summarized.And the significance of doing anti-seismic research,current research situation,and problems on utility tunnel.2)Combined with process of solving problems with the ABAQUS software,some basic theories of finite element method was introduced.A commonly used soil constitutive equation named D-P was recommend and the difference of the concrete plastic damage model present by the code for design of concrete structures and that provided by ABAQUS.Three kind of artificial boundary condition usually used in seismic response analysis of underground structure,which named viscous boundary,infinite boundary and viscoelastic boundary,were discussed.An example was given to test the effectiveness and accuracy of these boundaries.Contact models and their application in ABAQUS software were discussed.A reasonable model of typical utility tunnel system was built based on ABAQUS software through numerical simulation trial analysis.3)Seismic response analysis was conducted on typical utility tunnel system based on finite element method.The input are made of 8 natural ground motions with different spectrum.Each ground motion were adjusted to 0.05 g,0.1g,0.2g,0.3g,Which was 32 simulation conditions totally.By analyzing the horizontal displacement and their relative horizontal displacement of top plate and the bottom of utility tunnel,damage of utility tunnel,acceleration of bottom plate,basement and pipeline,stress of pipeline,this thesis focus on the regulation of the dynamic response of utility tunnel system and estimate its anti-seismic performance.4)The feature of the seismic response of pipelines put in utility tunnel and these buried directly were summarized through the comparison of their seismic response And some suggestions was given base on the result.