ANALYSIS OF THE LARGE DEFLECTION DYNAMIC RESPONSE OF RIGID-PLASTIC CIRCULAR PLATE RESTING ON FLUID

A study is presented for the large deflection dynamic response of rigid- plastic circular plate resting on potential fluid under a rectangular pressure pulse load. By virtue of Hankel integral transform technique,this interaction problem is reduced to a problem of dynamic plastic response of the plate in vacuum.The closed-form solutions are derived for both middle and high pressure loads by solving the equations of motion with the large deflection in the range where both bending moments and membrane forces are important.Some numerical results are given.

Numerical simulation of dynamic pore pressure in asphalt pavement

For studying the driving role of dynamic pressure in water-induced damage of asphalt pavement, based on the fast Lagrangian finite difference method and Biot dynamic consolidation theory, fluid-solid coupling analysis of the pavement is conducted considering asphalt mixtures as porous media. Results reveal that the development and dissipation of the dynamic pore pressure are coinstantaneous and this makes both the positive and negative dynamic pore pressure and seepage force alternate with time. Repetitive hydrodynamic pumping and sucking during moisture damage is proved. The dynamic pore pressure increases with vehicle velocity. Effective stress and deflection of pavement decrease due to the dynamic pore water pressure. However, the emulsification and replacement of the asphalt membrane by water are accelerated. The maximum dynamic pore pressure occurs at the bottom of the surface course. So it is suggested that a drain course should be set up to change the draining condition from single-sided drain to a two-sided drain, and thus moisture damage can be effectively limited.

Forced Vibration Analysis of Functionally Graded Anisotropic Nanoplates Resting on Winkler/Pasternak-Foundation

This study investigates the forced vibration of functionally graded hexagonal nano-size plates for the first time.A quasi-three-dimensional(3D)plate theory including stretching effect is used to model the anisotropic plate as a continuum one where small-scale effects are considered based on nonlocal strain gradient theory.Also,the plate is assumed on a Pasternak foundation in which normal and transverse shear loads are taken into account.The governing equations of motion are obtained via the Hamiltonian principles which are solved using analytical based methods by means of Navier’s approximation.The influences of the exponential factor,nonlocal parameter,strain gradient parameter,Pasternak foundation coefficients,length-to-thickness,and length-to-width ratios on the dynamic response of the nanoplates are examined.In addition,the accuracy of an isotropic approximate instead of the anisotropic model is studied.The dynamic behavior of the system shows that mechanical mathematics-based models may get better results considering the anisotropic model because the dynamic response can cause prominent differences(up to 17%)between isotropic approximation and anisotropic model.

Data Fusion about Serviceability Reliability Prediction for the Long-Span Bridge Girder Based on MBDLM and Gaussian Copula Technique

This article presented a new data fusion approach for reasonably predicting dynamic serviceability reliability of the long-span bridge girder.Firstly,multivariate Bayesian dynamic linear model(MBDLM)considering dynamic correlation among the multiple variables is provided to predict dynamic extreme deflections;secondly,with the proposed MBDLM,the dynamic correlation coefficients between any two performance functions can be predicted;finally,based on MBDLM and Gaussian copula technique,a new data fusion method is given to predict the serviceability reliability of the long-span bridge girder,and the monitoring extreme deflection data from an actual bridge is provided to illustrated the feasibility and application of the proposed method.