Solution of Navier-Stokes equations for fluids with magnetorheological compensation used in structures with energy dissipaters

The fixed-wall rectangular cavity flow problem is a classic problem that has been studied since the beginning of computational fluid mechanics. The present work aims to provide a numerical and computational solution of the Navier-Stokes equations using the finite difference method, applied to model the problem of a magnetorheological fluid in a rectangular cavity with a fixed wall in shock absorbers devices, used in civil structures that use energy dissipators.

Piedmont deposits as seismic energy dissipators, Sierras Pampeanas of Argentina

This study shows the neotectonic deformation occurred in the southern piedmont of the Cumbres Calchaquíes, in the Amaicha and Tafí valleys. Neotectonic deformation manifests itself through faults, folds and diversions of drainage channels. The Amaicha valley is bounded to the north by the Tafí del Valle fault and to the south by the Los Cardones fault. The Cumbres Calchaquíes ride over the Sierra de Aconquija through the Los Cardones and Carapunco faults. The Carapunco fault also has a synestral component, responsible for generating an imbricated system of contractional fractures. In the study region many earthquakes of ≥ 3 and ≥ 4 magnitude coincide with regional faults evidencing its neotectonic activity. The seismic energy dissipated through materials with less cohesion that form the fill of the valleys, generating discrete fault scarps and strongly folded conglomerate strata. The foothills deposits of the Cumbres Calchaquíes absorbed most of the seismic energy released during the reactivation of the faults. Tectonic activity is deforming 630 a BP deposits in the Cumbres Calchaquíes piedmont.

Optimization and Effectiveness of The Placement of Energy Dissipators In Rc Frame Structures

This document explores and analyzes the optimization of the use and placement of energy dissipators in the bays of frame structures located in seismic zones. This study may be applied to new and existing buildings. In order to do this, three RC frames of 5, 10 and 15 stories are analyzed and compared, using four brace arrangements (Chevron braces San Andrés cross and diagonal braces (two cases)). The behavior of these frames is analyzed in terms of modal parameters, capacity curves (Push-over) and dynamic analyses (Time-History). For the study, the Lorca record of mean magnitude was used, also in this case, hysteretic dissipators have been used as they are cheap and easy to install solutions. The efficiency of the energy dissipators is improved as the frames increase in height. In the lower height frames, the use of braced solutions without any device improves the structural behavior. The ductility of all frames increases with the placement of dissipators.

Cyclic Behavior and Simplified Design Method of Hybrid Rocking Columns with External Energy-Dissipators

In recent years, hybrid rocking columns incorporating post-tensioned (PT) tendons and energy dissipation devices become prevalent on account of the superior self-centering capacity. In this paper, the simplified analysis method based on interface section analysis is employed to conduct parametric analyses on the hybrid rocking columns with external buckling-restrained devices, which are adopted as the external energy-dissipators. The effects of four parameters including the aspect ratio, the initial PT force, the area of PT tendons and the area of energy-dissipators are investigated. Furthermore, a simplified design method for hybrid rocking columns with external energy-dissipators is proposed using the parametric analysis results. In the design procedure, the performance index [Formula: see text] is employed considering the requirement of residual drift. The efficiency of the design method is verified by a numerical design example to show the application. The results show that the design objectives of lateral force and residual drift can be achieved through a small number of iterations.

Experimental investigation on the effect of different slot shapes and configurations on scour dimension downstream of flip buckets

Flip buckets at the end of a spillway can dissipate the flood discharge energy. Compared to other energy dissipators, this is a cost-effective structure. The formation of a scour hole downstream of a flip bucket is a topic of interest among hydraulic engineers. The current study investigated scouring downstream of a flip bucket under two major scenarios: (i) free conditions, and (ii) slotted conditions with rectangular and triangular slots configured differently under four different discharge rates. In total, 20 experiments were conducted in this study. Results showed that the use of a deflector slot greatly affected the scour extent and depth, resulting in a greater scour reduction (53%) in the labyrinth rectangular slotted bucket compared to the solid bucket. The results were compared to empirical equations, and a high correlation was observed between them. In comparison, the Taraimovich equation produced more accurate results in control experiments, and the Damle-A and Damle-B equations produced more accurate results in experiments corresponding to labyrinth rectangular and triangular slotted buckets.

Seismic and Time History Performance of RCC Framed Buildings with and without Passive Energy Dissipators

Base isolation is an effective way to protect large structures from earthquake damage. It is a costly approach, as the entire structure must be supported on elastomeric or sliding bearings. Viscous dampers distributed throughout an otherwise conventional structure can achieve the same result at a significantly lower cost. Dampers are used to resist lateral forces coming on the structure. Dampers are the energy dissipating devices which also resist displacement of Reinforced Concrete (RC) buildings during an earthquake. These dampers help the structure to reduce buckling of columns thereby increasing the stiffness of the structure. During earthquakes, multi-storeyed buildings get damaged and as a result, large deformation occurs. Dampers reduce vibration and deformation of structural elements during an earthquake. Retrofitting buildings with fluid viscous dampers (FVDs) can improve Interstorey drifts and floor accelerations. In the present study, an RC framed building is modelled and analysed under Southern Sumatra and Chile earthquakes to evaluate the performance of the structure and its elements with and without energy dissipators. For the study, a model (G+19) with and without energy dissipators is modelled in ETABS. The seismic force is applied based on the time history data of the models pertaining to Southern Sumatra and Chile Earthquake. Response Spectrum analysis has been carried out to find the lateral displacements, storey shear and Base shear for the model with and without dampers. The lateral displacement, storey drift, storey shear and Base shear are found to less for the model with Linear FVDs when compared to the model with Non-Linear FVDs and without FVDs.