以某核电站海域工程取水明渠导流堤为背景,研究取水明渠堤头在地震作用下的动力响应规律,从结构的位移时程、结构变形、超孔压比、液化区域等方面定量评价取水明渠堤头结构的安全性。采用MIDAS/GTS NX TO FLAC3D的建模方法,结合PL-Finn...以某核电站海域工程取水明渠导流堤为背景,研究取水明渠堤头在地震作用下的动力响应规律,从结构的位移时程、结构变形、超孔压比、液化区域等方面定量评价取水明渠堤头结构的安全性。采用MIDAS/GTS NX TO FLAC3D的建模方法,结合PL-Finn液化后大变形本构模型,通过FLAC3D有限差分程序开展动力响应数值模拟。计算结果表明:砂土液化后发生流动使导流堤结构出现规律性残余变形,且随地震强度增加而变大;与基底输入地震动相比,在堤头结构顶部水平和竖直加速度放大2-3倍,且越靠近堤头顶部处加速度呈现出明显放大效应。综合判断地震产生的永久变形不至于使堤头结构向海侧滑移,不会影响到核电厂安全用水。本文研究成果可为类似项目抗震设计提供参考。展开更多
In order to obtain the seismic responses of the soil-rectangular tunnel structure,based on the PL-Finn constitutive model,four different conditions,namely,the liquefied soil around the rectangular tunnel,the liquefied...In order to obtain the seismic responses of the soil-rectangular tunnel structure,based on the PL-Finn constitutive model,four different conditions,namely,the liquefied soil around the rectangular tunnel,the liquefied soil below the rectangular tunnel,the liquefied soil on either side of the tunnel and the structure on non-liquefied soil,are compared.In accordance to the time at which a large deformation occurs,the possibility of destruction from hard to easy follows a descending order:the liquefied soil all around the structure,the liquefied soil on the bottom of the structure,and the liquefied soil on the two sides of the structure.The area of large deformation is mostly beneath the two arch angles of the tunnel floor.The soil on the two sides,especially close to the structure,is the hardest to liquefy and deform.The large deformation of soil caused by the liquefaction appears after the peak seismic value occurs.The higher the input seismic value is,the easier a large deformation can take place.With the same input of peak ground motion,the total displacement vector of the structure and differential displacement of the side-wall are in accordance with an order from large to small in the three situations:when the saturated sand is on two sides,all around the structure,and on the bottom of the structure.展开更多
文摘以某核电站海域工程取水明渠导流堤为背景,研究取水明渠堤头在地震作用下的动力响应规律,从结构的位移时程、结构变形、超孔压比、液化区域等方面定量评价取水明渠堤头结构的安全性。采用MIDAS/GTS NX TO FLAC3D的建模方法,结合PL-Finn液化后大变形本构模型,通过FLAC3D有限差分程序开展动力响应数值模拟。计算结果表明:砂土液化后发生流动使导流堤结构出现规律性残余变形,且随地震强度增加而变大;与基底输入地震动相比,在堤头结构顶部水平和竖直加速度放大2-3倍,且越靠近堤头顶部处加速度呈现出明显放大效应。综合判断地震产生的永久变形不至于使堤头结构向海侧滑移,不会影响到核电厂安全用水。本文研究成果可为类似项目抗震设计提供参考。
基金The National Natural Science Foundation of China(No.41572276)the National Key Research and Development Program of China(No.2017YFC0805400)
文摘In order to obtain the seismic responses of the soil-rectangular tunnel structure,based on the PL-Finn constitutive model,four different conditions,namely,the liquefied soil around the rectangular tunnel,the liquefied soil below the rectangular tunnel,the liquefied soil on either side of the tunnel and the structure on non-liquefied soil,are compared.In accordance to the time at which a large deformation occurs,the possibility of destruction from hard to easy follows a descending order:the liquefied soil all around the structure,the liquefied soil on the bottom of the structure,and the liquefied soil on the two sides of the structure.The area of large deformation is mostly beneath the two arch angles of the tunnel floor.The soil on the two sides,especially close to the structure,is the hardest to liquefy and deform.The large deformation of soil caused by the liquefaction appears after the peak seismic value occurs.The higher the input seismic value is,the easier a large deformation can take place.With the same input of peak ground motion,the total displacement vector of the structure and differential displacement of the side-wall are in accordance with an order from large to small in the three situations:when the saturated sand is on two sides,all around the structure,and on the bottom of the structure.
