CAJ | 학술논문

基于 ABAQUS 有限元软件平台，应用流固耦合两相介质动力模型孔压单元模拟场地饱和土体，进行了饱和土体-地下结构地震反应的计算研究。结果表明：在地震输入的最后时刻结构的两侧底角区域应力值最大；土体的孔隙压力和竖向位移主要集中在结构下方的区域，结构两侧土体的孔压与竖向位移呈对称分布；场地土体的竖向位移随深度的增加逐渐减小；体系最大地震反应出现的时刻对应于输入地震动的最大加速度出现的时刻。表明了流固耦合两相介质动力模型孔压单元在饱和土体-地下结构体系地震反应研究中的有效性。
기우 ABAQUS 유한원연건평태，응용류고우합량상개질동력모형공압단원모의장지포화토체，진행료포화토체-지하결구지진반응적계산연구。결과표명：재지진수입적최후시각결구적량측저각구역응력치최대；토체적공극압력화수향위이주요집중재결구하방적구역，결구량측토체적공압여수향위이정대칭분포；장지토체적수향위이수심도적증가축점감소；체계최대지진반응출현적시각대응우수입지진동적최대가속도출현적시각。표명료류고우합량상개질동력모형공압단원재포화토체-지하결구체계지진반응연구중적유효성。
In China,various transportation facilities have been built on a large scale.Sea-crossing tunnel projects are constructed in many coastal cities,and many underground structures are built on the soft soil foundation in the south region.These are all underground structures on saturated soil,and China lies in the Pacific Ring of Fire,with many cities located in the high-intensity earthquake zone,so the seismic security of underground structures such as tunnels and subway stations is an important subject.The key is to make an accurate calculation of the dynamic re-sponse of the underground structure to the earthquake load.The dynamic response of an under-ground structure in a saturated soil site is very different from that in other types of soil sites. Therefore,the seismic response of underground structure in the saturated soil should be studied with the right calculation model and analyzing method. <br> At present,one widely used method is numerical simulation and calculation.Depending on the soil calculation model it employs,the analytic method can be classified into three types:the total stress method,simplified effective stress method,and fluid-solid coupling dynamic model method.The fluid-solid coupling model,which takes into account the coupling of fluid-solid dy-namic response,is a theoretically complete calculation model.Therefore,the method based on the fluid-solid coupling dynamic model is theoretically sound and more accurate.In general,the dynamic response of an underground structure in a saturated soil site needs further study.In this paper,the seismic response of an underground structure in saturated soil is studied based on the fluid-solid coupling dynamic model and ABAQUS in order to get a complete view of the character-istics and rules of the seismic response. <br> We conduct a simulated calculation of the seismic response of an underground structure in saturated soil,with the site soil simulated by the pore pressure element deduced from the fluid-solid coupling dynamic model of fluid-saturated porous media.The example chooses the seismic record of the N-S components of the Ninghe earthquake (magnitude 6.9 aftershock of the Tang-shan earthquake)as the seismic input.From the calculation,we obtain the distribution chart of soil pore pressure,vertical displacement of soil-tunnel system,and von Mises stress on the struc-ture.The calculation results illustrate that by the end of the seismic input,the stress distribution is symmetrical.The stress distribution concentrates in the base area of the two sides,and the wa-ter pressure mainly distributes in the base and side areas.The pore pressure and vertical displace-ment of the site soil are maximal in the base area and decrease gradually in the side area.With in-crease of depth,the vertical displacement of the site soil decreases gradually.The pore pressure and vertical displacement of the site soil distribute symmetrically.The greatest seismic response occurs when the acceleration of the input earthquake wave reaches the maximum.The calculation results also indicate that the pore pressure element deduced from the fluidvsolid coupling dynamic model of the fluid-saturated porous model can be employed as an effective calculation model for the study of all types of underground structures in saturated soil sites.