Currently, there is no general agreement on a theory describing the response of reinforced concrete members without web reinforcement. Many structural systems rely on design is usually performed using empirical or semi-empirical expressions provided by codes of practice that do not consider the influence of many governing parameters. In this paper, a comparison between values of current experimental shear strength and those of various international design approaches [1-10] have been calculated and analyzed on 18 simple span HSRC deep beams without web reinforcement were tested under monotonic two point loads at the mid span to examine the contribution of various parameters on the shear capacity of HSRC beams like; f’cu=50 MPa, three values of tension reinforcement (0.73%,1.21% &1.83%) and shear span to effective depth ratio ( 2,1.5 &1) were selected to mainly study the behavior of deep beams, where typical shear failure can be anticipated.

Currently, there is no general agreement on a theory describing the response of reinforced concrete members without web reinforcement. Many structural systems rely on design is usually performed using empirical or semi-empirical expressions provided by codes of practice that do not consider the influence of many governing parameters. In this paper, a comparison between values of current experimental shear strength and those of various international design approaches [1-10] have been calculated and analyzed on 18 simple span HSRC deep beams without web reinforcement were tested under monotonic two point loads at the mid span to examine the contribution of various parameters on the shear capacity of HSRC beams like; f’cu=50 MPa, three values of tension reinforcement (0.73%,1.21% &1.83%) and shear span to effective depth ratio ( 2,1.5 &1) were selected to mainly study the behavior of deep beams, where typical shear failure can be anticipated.

Currently, there is no general agreement on a theory describing the response of reinforced concrete members without web reinforcement. Many structural systems rely on design is usually performed using empirical or semi-empirical expressions provided by codes of practice that do not consider the influence of many governing parameters. In this paper, a comparison between values of current experimental shear strength and those of various international design approaches [1-10] have been calculated and analyzed on 18 simple span HSRC deep beams without web reinforcement were tested under monotonic two point loads at the mid span to examine the contribution of various parameters on the shear capacity of HSRC beams like; f’cu=50 MPa, three values of tension reinforcement (0.73%,1.21% &1.83%) and shear span to effective depth ratio ( 2,1.5 &1) were selected to mainly study the behavior of deep beams, where typical shear failure can be anticipated.

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This paper addresses the optimal distributed generation sizing and siting for voltage profile improvement, power losses, and total harmonic distortion (THD) reduction in a distribution network with high penetration of non-linear loads. The proposed planning methodology takes into consideration the load profile, the frequency spectrum of non-linear loads, and the technical constraints such as voltage limits at different buses (slack and load buses) of the system, feeder capacity, THD limits, and maximum penetration limit of DG units. The optimization process is based on the Genetic Algorithm (GA) method with three scenarios of objective function: system power losses, THD, and multi-objective function-based power losses and THD. This method is executed on the IEEE 31-bus system under sinusoidal and non-sinusoidal (harmonics) operating conditions including load variations within the 24-hr period. The simulation results using Matlab environment show the robustness of this method in optimal sizing and siting of DG, efficiency for improvement of voltage profile, reduction of power losses, and THD. A comparison with particle swarm optimization (PSO) method shows that the proposed method is better than PSO in reducing the power losses and THD in all suggested scenarios.

Laminar natural convection in differentially heated (β = 0°, where β is the inclination angle), inclined (β = 30° and 60°), and bottom-heated (β = 90°) square enclosures filled with a nanofluid is investigated, using a two-phase lattice Boltzmann simulation approach. The effects of the inclination angle on Nu number and convection heat transfer coefficient are studied. The effects of thermophoresis and Brownian forces which create a relative drift or slip velocity between the particles and the base fluid are included in the simulation. The effect of thermophoresis is considered using an accurate and quantitative formula proposed by the authors. Some of the existing results on natural convection are erroneous due to using wrong thermophoresis models or simply ignoring the effect. Here we show that thermophoresis has a considerable effect on heat transfer augmentation in laminar natural convection. Our non-homogenous modeling approach shows that heat transfer in nanofluids is a function of the inclination angle and Ra number. It also reveals some details of flow behavior which cannot be captured by single-phase models. The minimum heat transfer rate is associated with β = 90° (bottom-heated) and the maximum heat transfer rate occurs in an inclination angle which varies with the Ra number.

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