دانلود رایگان مقاله انگلیسی یک عنصر ماکرو برای مدل سازی کجی فونداسیون سطحی تحت بار لرزه ای - الزویر 2018

ABSTRACT

This paper presents a new soil-foundation macro-element model to allow efficient and sufficiently accurate consideration of soil-foundation-structure interaction in structural analysis. The model makes use of two constitutive models, a plasticity model which models the soil inelastic deformation, and an elastic uplift model, which captures the geometric non-linearity during uplift of the foundation. Further considerations are made to allow the macro-element to be efficiently implemented in a particular non-linear finite element software (Ruaumoko3D). Two experimental centrifuge tests are simulated using the proposed macro-element: one of a bridge pier and one of a one-bay, one-storey frame structure. The simulated results are compared to the experimental behaviour to demonstrate the accuracy of the numerical model.

5. Conclusions

This paper presents a macro-element formulation for predictive assessment of the effects of SFSI. The model captures the major nonlinear aspects of SFSI through two interacting constitutive models. The plasticity model captures the effects of soil yielding, while the uplift model captures the geometric non-linearities during footing uplift. The macro-element was implemented in the time history analysis software Ruaumoko3D and numerical simulations were compared to two sets of seismic centrifuge tests. In the first experiment, a pier structure was shaken to levels close to toppling using both recorded and pulse type ground motions. The second experiment was a one bay, single storey frame structure with a non-linear superstructure and isolated footings, exposed to recorded ground motions at varying levels of intensity. In both cases the macro-element model provided suitable simulation of the transient behaviour of the foundation and superstructure. The model also provided reasonable estimates of settlement and in some cases the residual foundation rotation was also modelled accurately. The macro-element provides an intuitive and numerical efficient tool for simulating complex non-linear soil-foundation-structure interaction. The validation and continued development of soil-foundation macro-elements is a promising path forward to allow SFSI to be widely considered and understood in structural engineering. The development and implementation of this macro-element was a key step towards the development of integrated displacement-based design and assessment procedure for building-foundation systems [24,25].