高压缩性混凝土材料在隧道穿越断层带的应用及减震效果研究

Application of High Compression Ratio Concrete on Tunnel Crossing Fault Zone and Damping Effect Study

在大量的隧道建设中,特别是长大隧道,不可避免地会在活断层附近和高烈度地震区修建,地震中隧道穿越活动断层段结构破坏现象严重,衬砌结构的抗减震设计问题尤为突出。为了缓和断层位移对隧道的损伤,提出使用高压缩性混凝土作为吸收层的减震设计建议,通过数值模拟对比分析使用高压缩性混凝土作为吸收层的地震响应结果。结果表明,采用高压缩性混凝土作为吸收层具有充分屈服后吸收断层位移的变形特性和抑制列车荷载产生过大变形的初始刚度。通过改变高压缩性混凝土的球壳种类、充填率和砂浆配比等来改变其刚性。但W/C不应过高,否则会造成多壳砂浆的单轴抗压强度不能承受列车的荷载,有可能造成隧道的损伤。

In a mass of tunnel construction, especially in long and high seismic risk zone is not inevitable. Serious damage of tunnels and deep buried tunnels, crossing active faults were suffered in active faults. Seismic design of tunnel lining structure hecomes particularly prominent. In order to reduce the damage on tunnel by fault displacement, seismic design using high compression ratio concrete was given. Based on analysis of seismic response results of tunnel structure using high compactness concrete as the absorbing layer, conclusion was made~ for the case of using high compactness concrete as the absorbing layer, the layer possess the ability absorbing fault displacement after full yield and the stiffness to restrain oversize displacement may happen under the train load. By changing spherical shell type, filling ratio, mortar proportioning of high compactness concrete, the stiffness can be changed. The water-cement ratio W/C should not be too high, which can cause compression strength of mortar cannot bear the train load and tunnel structure damage.