The dynamical responses of railway track has been carried out by different ways. In this work, developing an analytical model for the ballasted which includes two rails connected to sleeper, a fast method calculated dynamic is presented. rail modelled as infinite beams posed on periodically supports are rested viscoelastic foundation. We consider equation in steady-state subjected moving loads....

Most of the Codes of Practice (API, BSI, DnV, NPD) uses Morison's equation to estimate hydrodynamic loads on fixed and moving offshore structures. The significant difference in the prediction of the loads mainly arises from the assumption of the values of hydrodynamic coefficients. In this paper by analysing a full scale set of data in large KC's numbers collected from Delta Wave Flume in the N...

The vibrations produced by trains include two parts which are deterministic and random vibrations. Due to variation of dynamic loads and patterns of load-time, the random vibration of moving train is one of the most important issues in the field of railway engineering. One of the important sources in producing the train vibrations is rail roughness and irregularities. In this paper, responses o...

Effect of altitude is discussed in the unsteady separation of multi stage rockets. Axisymmetric, unsteady and turbulent Navier stokes equations are solved numerically. The governing equations are split into a hyperbolic inviscid part and a parabolic diffusion part. The hyperbolic part is solved by an explicit second-order time and space of Godunov-type scheme. Moving mesh and moving boundary al...

Occurrence of top down and bottom up fatigue cracking in asphaltic pavements is common. Conventional pavement analysis methods ignore the existence of cracks in asphaltic layers. However, it seems that the responses of cracked pavement would not be the same as a pavement without crack. This paper describes effects of crack type, position and length, and vehicles tire inflation pressure and axle...

Using harmonic differential quadrature (HDQ) method, nonlinear vibrations and instability of a smart composite cylindrical shell made from piezoelectric polymer of polyvinylidene fluoride (PVDF) reinforced with boron nitride nanotubes (BNNTs) are investigated while clamped at both ends and subjected to combined electro-thermo-mechanical loads and conveying a viscous-fluid. The mathematical mode...

This paper explores the application of smartphones for human-induced loads measurements. Preliminary tests were carried out to select proper smartphones and data acquisition software. Shaking table tests were then conducted on selected smartphones to measure sinusoidal waves of various frequencies, sinusoidal sweep waves and earthquake waves. Comparison between the smartphones’ measurements and...

The least successfully modeled joint complex has been the shoulder. In multi-segmented mathematical shoulder models rigid beams (the bones) act as a series of columns or levers to transmit forces or loads to the axial skeleton. Forces passing through the almost frictionless joints must, somehow, always be directed perfectly perpendicular to the joints as only loads directed at right angles to t...