含软弱夹层场地中埋地管道的地震反应特性研究

Seismic Response Characteristics of the Buried Pipeline in Soil with Soft Interlayer

为了研究含软弱夹层场地中埋地管道的地震反应特性,基于管土接触模型,运用ADINA软件,采用非线性分析,研究埋深、厚度和倾角等因素对含软弱夹层场地中埋地管道地震反应的影响规律。结果表明:软弱夹层各因素对埋地管道地震动力响应产生影响不同,一定厚度和埋深条件下,软弱夹层具有隔震作用,当软弱夹层的存在增大其场地不均匀程度,则会对埋地管道地震动响应具有非常不利的影响;管道有效应力和位移随着软弱夹层厚度的增大而减小,当厚度达到一定值时,软弱夹层起到一定的缓冲作用;管道有效应力和位移随着软弱夹层埋深的增大而减小,但影响程度小于夹层厚度所产生的;软弱夹层因倾角变大增大了场地不均匀程度,导致管道有效应力和位移变大。

In order to study the seismic response characteristics of the buried pipeline in soil with soft interlayer,the software ADINA and nonlinear constitutive model was adopted in this paper. The interaction model was also utilized to simulate the contact of pipeline and soil. The influence of different factors including the buried depth,the soft interlayer thickness and the dip angle on seismic response of pipeline was obtained. Results show that the influence of the soft interlayer indexes on the seismic dynamic response of buried pipeline is different. The soft interlayer has an effect of isolation with a proper thickness and a suitable buried depth. When enhancing the inhomogeneity of the ground,soft interlayer will have unfavorable impact on the seismic response of the buried pipeline. The effective stress and deformation of the pipeline decrease with the increase of the soft interlayer thickness. The soft interlayer plays a certain buffering role when its thickness reaches a certain value. The effective stress and deformation of the pipeline decrease with the increase of the buried depth of the soft interlayer,but the influence degree is less than that of the interlayer thickness. The effective stress and deformation of the pipeline increase with the increase of the dip angle of the soft interlayer which increases the inhomogeneity of the ground.