The methods for treatment of earthquake input and modeling of radiation damping in infinite foundation were established based on cylindrical wave equation.

The calculation of the earthquake response of Longjiang Arch Dam as a case study shows that the infinite foundation radiation damping associated with wave propagation away from the dam decreases the dynamic arch cantilever stress by 40%-50% as compared with massless foundation models and results in obvious decrease of maximal principal tensile stress and maximal principal compressive stress of the dam in static and dynamic composite states under normal water storage level and dead water level.

The dynamic analysis of damfoundationreservoir system of an arch dam was performed in this paper, using a numerical model considering infinite foundation radiation damping and contraction joints' nonlinearity and freefield earthquake input. A series of calculating cases were studied with or without foundation radiation damping under different reservoir water levels.

In this method,a finite domain was obtained by truncation of the infinite foundation,and the truncated foundation was simulated by a series of dashpots and springs along the boundaries. Then,the earthquake inputs on the boundary with incident waves were simulated with an equivalent force directly proportional to the velocity of incident waves.

The structure-soil dynamic interaction is mainly confined in frequency domain because of the difficulty of determination of dynamic effects of infinite medium on structural response, which makes most of the dynamic interaction analysis methods invalidated for nonlinear problems.

Damping Extraction Method is an effective simple procedure, which can simulate the dynamic properties of non-homogeneous infinite medium by applying artificial damping and then shifting the frequency along frequency axis. Based on DSEM, it is convenient to get dynamic interaction force in time domain acting on interface between unbounded rock and structure.

The radiation damping induced by an infinite medium has great effects on the dynamic response of underground structures,which is usually added on the nodes at the outer boundary of the structures in a simplified model.

Taking advantages of the scaled boundary finite element method(SBFEM),the influence of the foundation inhomogeneity on the seismic response of high arch dams is studied. The arch dam,the unbounded foundation and the reservoir are all modeled by the SBFEM.

The seismic actions are usually applied to structure by transforming the seismic displacement,velocity and acceleration to external loads acting on the boundary in almost all the methods for the dynamic structure-foundation interaction analysis because of frequency-dependant feature of infinite soil impedance.

A method for nonlinear dynamic response analysis of semi-infinite foundation using mapping

Using linear and nonlinear constitutive models, the responses of semi-infinite foundation soil are computed by the authors proposed method with a small mesh model and an extensive mesh model.

The stability of a jet in an infinite medium increases with increase in the viscosity of both the jet and the medium [2, 3].

Unlike the cometary coma, the regolith is an optically semi-infinite medium, where the interaction between particles is significant.

Mass Transfer to a Semi-infinite Medium Accompanied by Reversible Chemical Reactions

A mathematical method is developed for deriving asymptotic relationships for the mass-transfer acceleration factor at the boundary of a semi-infinite medium.

Statistical properties of resonance radiation selectively reflected from a cold semi-infinite medium

Geological conditions of the dam canyon are usually very complicated; however, in the literature, the damfoundation interaction analysis is often carried out based on the premise of a homogeneous unbounded foundation.

In order to satisfy the similarity requirement of SBFEM and simplify the computational effort, a subdomain approach and a conical representation of an unbounded foundation were proposed.

It was found that a homogeneous idealization of the unbounded foundation may sometimes greatly underestimate the maximum earthquake stress response of the dam.

Coupling with the equation of dam-unbounded foundation interaction, it can effectively carry out the earthquake response analysis of dam-reservoir-foundation system.

The numerical method employed is a combination of the time domain semi-analytical boundary element method (SBEM) used for the semi-infinite soil medium and the semi-analytical finite element method (SFEM) used for the three-dimensional structure.

The structures are discretized by finite elements, and the infinite soil is represented by boundary elements.

Because of this, the behavior of such a semi-infinite soil mass can be idealized as a one-dimensional soil column.

So far,to the authors' knowledge,the application of elastoplastic soil model in the superstructure-foundation-soil interaction has not yet been worked out in China. The purpose of this paper is to study whether the elastoplastic soil model can be used or not in the interaction between silty-sand and box foundation for tall buildings in Shanghai. Now the comparison between the calculated results from incremental method and the measured results in the similar foundation soil gives sufficient proof that this model...

So far,to the authors' knowledge,the application of elastoplastic soil model in the superstructure-foundation-soil interaction has not yet been worked out in China. The purpose of this paper is to study whether the elastoplastic soil model can be used or not in the interaction between silty-sand and box foundation for tall buildings in Shanghai. Now the comparison between the calculated results from incremental method and the measured results in the similar foundation soil gives sufficient proof that this model can be used under some simplified assumptions.The reaction forces ( contact pressures ) and foundation settlement agree reasonably with those measured in similar foundation soil.It is worth mentioning that the distribution of reaction forces is essentially different from that of elastic half space model.

In dealing with problems of infinite foundation with tectonic faults which are extending to infinite distance, a model employing seven-node infinite element coupling with isoparametric finite element is presented. Effects of locations and strikes of faults on the stress distribution of gravity dams are studied. Great advantages of saving computer time significantly and improving accuracy are obtained by using this method to model foundation and tectonic problems.

In this paper the BEM based on fundamental solutions of infinte domain and semi-infinite domain is developed, which is applicable for solving problems of statical interaction between structures and semi-infinite plane base. As long as this method is adopted, elements are idealized only on the structure surface, on the base surface with side loads and on interfaces between structures and the base, and thus the effect of the entire semiinfinite base is incorporated. In comparison with the general FEM and BEM,...

In this paper the BEM based on fundamental solutions of infinte domain and semi-infinite domain is developed, which is applicable for solving problems of statical interaction between structures and semi-infinite plane base. As long as this method is adopted, elements are idealized only on the structure surface, on the base surface with side loads and on interfaces between structures and the base, and thus the effect of the entire semiinfinite base is incorporated. In comparison with the general FEM and BEM, this method made a feature of less amount of data processed before and after computation, less internal storage and less computer time required. At the same time the accuracy is considerably improved. Various contact conditions on interfaces are discussed here. The constant body force is converted into boundary traction during the application of BEM.