摘要
本文对一种地基无限域的动力模型——映射动力无穷元与有限元耦合模型进行总结.通过阐述映射动力无穷元的基本原理,并利用三维地基无限域中的波动问题验证这一模型具有的计算精度,说明这类数值模型具有以下优点:(1)由于用有限元模拟近域,用无穷元模拟远域,故可适应于模拟多种土层和复杂地基的情况.(2)无穷元的应用消除了波在有限元边界上人为的反射效应,保证了数值解答的计算精度;另一方面,又大大减小了有限元的模拟范围,节省了数值计算工作.(3)由于采用了映射技术,地基中不同波数的模拟可通过调整单元边中结点整体座标来实现,使无穷元在公共边界上的位移协调性得以保持.
In this paper, a dynamic coupling model of finite and infinite elements for simulating infinite foundations is summarized. Through the derivation of basic formula and verification of computational accuracy of wave propagation in a 3-D infinite foundation, advantages of the presented model can be summarized as follows: (1)By using the finite elements to discre-tize the near field foundation and using the infinite elements to evaluate the far field effects, this model is suitable for simulating multiple layers and complicated foundation. ( 2 )The use of infinite elements for modelling wave radiation eliminates the effects of artificial reflection of waves from finite element boundary, therefore the computational accuracy can be assured. Meanwhile, the spatial range of finite element discretization is significantly reduced and computational economy can be achieved. (3) Using the mapping technique, simulation of different wave numbers can be realized by changing the global coordinates of middle nodes of elements, therefore the displacement compatibility on common boundary of infinite elements can be retained.
出处
《水利学报》
EI
CSCD
北大核心
1990年第6期20-27,共8页
Journal of Hydraulic Engineering
