| The Huangcaoping tunnel locates 300 or 400m far away from the Batang fault, a Recent Epoch active fault, and the basic seismic intensity is 9. It is the first tunnel built along fault in our country, which cause us to worrying about safety of the tunnel projects. This paper is research on Huangcaoping tunnel, and geology investigation, datum analysis and numerical modeling are applied to analyze seismic damage characteristics and dynamic effective rules of tunnels in and out countries. Moreover, seismic dynamic response and shock absorption measures are deeply studied and discussed. The chiefly study works and conclusions are summarized as following:1. Based on the former study, the generalized geological model has been built and active characteristics and the dynamic characteristic of faults are summarized in the tunnel location. It is Batang fault and Jinshajiang fault that control stability of the tunnel.2. Based on many seismic damages analyses of subway in and out countries and tunnels in mountainous area, forms and characteristics of seismic damages about the two kinds of linear structures are summarized. The mechanism of seismic damages to tunnels is chiefly concluded as following: a. Vibration-creep, b. Vibration-liquation, c. Vibration-slump, d. Vibration-shear, e. Vibration-tensile and shear. The effects of many factors on seismic damages to tunnels such as seismic intensity, amplitude of seismic wave, magnitude, intersecting relations with the tunnel, depth of burial, lithological characters of the stratum, geological conditions and framework of underground structure are analyzed.3. Taking Huangcaoping tunnel as geological archetype, unlimited field of rock mass and the process of dynamic response of the seism are simulated using FLAC-3D (Program of Lagrange finite difference). The influence to tunnel-liner, country rock earthquake accelerated speed and stress-displacement response has been studied that the factors such as earthquake shaking direction, seismic intensity, depth of burial and geological conditions etc. By way of changing cave shape structure, liner stiffness and setting up the movement joint analyze the effect and path to the tunnel shock absorption. The main research findings is:(1) In the free field, the secret structure doesn't influent the shake characteristic of country rock which following the law of earthquake wave travel. And the shake law of tunnel lining cutting is controlled by the shake property of country rock.(2) The earthquake dynamic response analysis indicates: a. The change of earthquake wave travel orientation will cause the big change of deform-destruction method. b. The destructiveness of the seismic wave of parallel travel on ground surface is better than of the seismic wave of vertical travel, and of vertical travel is bitter than of parallel travel in the tunnel figure. c. The displacement of the tunnel-liner will increase, which causing by earthquake. This law is clear on the tunnel arch crown. d. The earthquake reaction of the tunnel figure isn't big change that the depth of burial is greater than 50m. e. What suffers earthquake damage is also more small...
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