【摘要】 近年发生的大地震中,隧道在断层破碎带的破坏现象严重,衬砌结构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,提出由平滑层、吸收层、接头、去摩擦层等4个单元构成的减震设计建议。通过解析使用高压缩性混凝土(水灰比为W/C=50%)、发泡苯乙烯(EPS)作为吸收层的地震响应结果,得出以下结论:采用发泡苯乙烯(EPS)作为吸收层,其初始刚度小,减震效果明显,但在列车荷载作用下有可能产生过大的变形;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,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。本文使用W/C=50%时对断层位移小于1.0 m时缓和效果较好。更多还原

【Abstract】 Tunnels have suffered serious damage in active fault and fracture zones during earthquakes in recent years.Seismic design of tunnel lining structure becomes particularly prominent.In order to reduce the damage of the tunnels by fault displacement,a piece of advice for the seismic design is proposed,that is,it is composed of smooth layer,absorbing layer,joint and friction-eliminating layer.Based on the analysis of seismic response results of tunnel structure using high compactness concrete(water cement ratio of 50%) as the absorbing layer,as well as using foaming styrene(EPS) as the absorbing layer,conclusions are drawn as follows: for the case of using foaming styrene(EPS) as the absorbing layer,the initial stiffness is low,the damping effect is obvious,but too much displacement may happen under the train load.For the case of using high compactness concrete as the absorbing layer,the layer possesses 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 should not be too high,which may cause compression strength of mortar not to bear the train load and tunnel structure damage.The water cement ratio of 50% is satisfactory under the fault displacement of less than 1.0 m.更多还原