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This paper investigates the seismic performance of prefabricated segmental bridge columns (PSBCs) with hybrid post-tensioned tendons and energy dissipation (ED) bars under cyclic loading. PSBCs with unbonded and hybrid bonded prestressed tendons and columns incorporating ED bars are designed to improve the lateral strength, energy dissipation, and limit the residual drift. The PSBCs under cyclic loading were investigated using the three-dimensional finite element (FE) modeling platform ABAQUS. The FE model was calibrated against experimental results, with an overall error of less than 10%. The seismic performance of the proposed PSBCs was evaluated based on critical parameters, including lateral strength, residual plastic displacement, and the energy dissipation capacity. The results show that bonding the tendons in the plastic hinge region as opposed to the overall bonding along the column leads to a better cyclic performance. The lateral strength, and recentering abilities are further improved by bonding tendons up to 2/3 of the length in the plastic hinge region, along with 100–300 mm in the footing. It was also found that selecting a longitudinal length of ED bars crossing multiple precast segmental joints and having a circumferential spread of 70–90% of core concrete results in a higher bearing capacity and energy dissipation compared to ED bars crossing the single joint. [ABSTRACT FROM AUTHOR]

In this article, we deal with prescribed exponential surface temperature and prescribed exponential heat flux due to micropolar fluids flow on a Riga plate. The flow is induced through an exponentially stretching surface within the time-dependent thermal conductivity. Analysis is performed inside the heat transfer. In our study, two cases are discussed here, namely prescribed exponential order surface temperature (PEST) and prescribed exponential order heat flux (PEHF). The governing systems of the nonlinear partial differential equations are converted into nonlinear ordinary differential equations using appropriate similarity transformations and boundary layer approach. The reduced systems of nonlinear ordinary differential equations are solved numerically with the help of bvp4c. The significant results are shown in tables and graphs. The variation due to modified Hartman number M is observed in [theta] (PEST) and [phi] (PEHF). [theta] and [phi] are also reduced for higher values of the radiation parameter [T.sub.r]. Obtained results are compared with results from the literature. Key words: micropolar fluid, PEST and PEHT, variable thermal conductivity, Riga plate, numerical method. Nous nous penchons ici sur les surfaces a etirement exponentiel prescrit et sur les flux de chaleur a variation exponentielle prescrite, suite a l'ecoulement d'un fluide micropolaire sur une plaque de Riga. Le flot est induit par une surface en etirement exponentiel avec une conductivite thermique dependante du temps. Nous completons une analyse du transfert de chaleur et dans cette etude, deux cas classiques sont discutes, nommement (i) en prescrivant l'ordre exponentiel de la temperature de la surface (PEST) et (ii) en prescrivant l'ordre exponentiel du flux de chaleur (PEHF). Les equations directrices du systeme sont des equations non lineaires aux derivees partielles, qui sont converties en equations differentielles ordinaires non lineaires via des transformations appropriees de similarite, avec approximation par couche limite. Ces equations sont alors solutionnees numeriquement a l'aide de l'ensemble logiciel bvp4c. Les resultats pertinents obtenus sont presentes a l'aide de tables et de graphiques. Nous observons la variation de [theta] (PEST) et de [phi] (PEHF) suite au changement du nombre de Hartman M. De plus [theta] et [phi] diminuent pour de plus hautes valeurs du parametre de radiation [T.sub.r]. Ces resultats sont compares avec d'autres retrouves dans la litterature. [Traduit par la Redaction] Mots-cles: fluide micropolaire, PEST, PEHF, conductivite thermique variable, plaque de Riga, methode numerique., 1. Introduction Micropolar fluids drew attention from researchers due to their many applications in different fields, e.g., industry, manufacturing, and engineering. Micropolar fluids show high resistance in fluid motion when [...]

The physical model of the micropolar hybrid nanofluid flow with magnetohydrodynamic and thermal slip effects is considered. The flow of three-dimensional stagnation point of micropolar hybrid nanofluid past a circular cylinder is also taken into account. The flow model is controlled through partial differential equations. These equations are highly nonlinear in character and reduce to ordinary differential equations through applying the suitable similarity transformation. The reduced system is solved numerically using the shooting technique. The mutual effects are presented using graphs while comparative numerical results are presented in the tables. The diverse physical parts of the issue have been talked about. This study aims to investigate the solid nano-sized particle on the surface of a circular cylinder having sinusoidal variation. These nanosized particles are used to analyze the heat transfer improvement of micropolar hybrid nanofluid as compared to micropolar nanofluid. Key words: hybrid nanofluid, MHD, shooting method, micropolar fluid, thermal slip. Nous examinons ici le modele physique du flot d'un nanofluide hybride micropolaire avec effets magnetiqueshydrodynamiques et de glissement thermique. Nous tenons compte du flot d'un point de stagnation en 3D du nanofluide hybride micropolaire passant un cylindre circulaire. Le modele de flot est decrit par des equations differentielles partielles, qui sont tres non lineaires et sont reduites en equations differentielles ordinaires parune transformation de similarite appropriee. Ce dernier systeme est solutionne numeriquement par methode de tir. Les effets mutuels sont presentes graphiquement, alors que les effets comparatifs le sont a l'aide de tables. Les differentes parties physiques du probleme ont ete analysees. Cette etude examine la nanoparticule solide sur la surface d'un cylindre circulaire ayant une variation sinusoidale. Nous utilisons ces nanoparticules pour analyser l'amelioration du transfert de chaleur du nanofluide hybride micropolaire compare au nanoifluide micropolaire. Mots-cles: fluide micropolaire, nanofluide hybride, glissement thermique, methode de tir., 1. Introduction The boundary-layer concept has been successfully applied to non-viscous fluid models and has obtained massive attention throughout the previous few decades. Micropolar fluid is one of the important [...]