The purpose of this paper is concerned with the mathematical model development issues, necessary for a better prediction of dynamic responses of articulated rotor helicopters. The methodology is laid out based on mathematical model development for an articulated rotor helicopters, using the theories of aeroelastisity, finite element and the time domain compressible unsteady aerodynamics. The he...

progressive collapse is defined as the spread of an initial failure from element to element, eventually resulting in the collapse of an entire structure or a disproportionately large part of it. the current progressive collapse analyses and design methods in guidelines and codes focus on the alternate load path method. this method is suitable especially in the case of blast-induced progressive ...

The knee bracing steel frame (KBF) is a new type of energy dissipating frame which enjoys exceptional ductility and lateral stiffness. Rather than the beam-column joint, one end of the diagonal brace in KBF is attached to the knee element. Indeed, the knee element as a hysteretic damper is designed and detailed to behave like a structural fuse by sustaining controlled inelastic deformations as ...

Recent investigations have shown that the influences of Soil-Structure Interaction (SSI) may be detrimental to the seismic response of structure, and hence neglecting this phenomenon in analysis and design may lead to an un-conservative design. The objective of this paper is to quantify the effects of nonlinear soil-structure interaction on the seismic response of a low-rise special moment fram...

endurance time (et) method is a relatively new performance-based earthquake method for structural evaluation and design. in this method, the structure is subjected to a gradually intensifying accelorogram(s) and its performance is assessed based on the maximum time duration that it can meet the specified performance objectives. using moment-resisting and braced frames which are rehabilitated by...

The linear dynamic relationship between systemic arterial blood pressure (ABP) and cerebral blood flow velocity (CBFV) was studied by time- and frequency-domain analysis methods. A nonlinear moving-average approach was also implemented using Volterra-Wiener kernels. In 47 normal subjects, ABP was measured with Finapres and CBFV was recorded with Doppler ultrasound in both middle cerebral arteri...

Incremental Dynamic Analysis (IDA) procedure is now considered as a robust tool for estimating the seismic sidesway collapse capacity of structures. However, the procedure is time-consuming and requires numerous nonlinear response-history analyses. This paper proposes a simplified Modal Pushover Analysis (MPA) procedure for IDA of RC moment-resisting frames. The proposed method uses the dynamic...

Due to their dual behavior under tension and compression, structures with tension-only members show non-linear behavior. To analize such structures, it is necessary to use a nonlinear analysis scheme. Nonlinear analysis methods generally use gradual loading techniques with/without modification of stiffness matrix of the structure. These methods, in addition to being time consuming algorithms, a...