Plastic hinge properties play a crucial role in predicting the nonlinear response of structural elements. The plastic hinge region of reinforced concrete normal beams has been previously studied experimentally and analytically. The main objective of this research is to evaluate the behavior of the plastic hinge region of reinforced concrete deep beams and its comparison with normal beams through finite element simulation. To do so, ten beams contain six deep beams, and four normal beams, under concentrated and uniformly distributed loading, are investigated. Lengths in the plastic hinge region involving curvature localization, rebar yielding, and concrete crushing zones are studied. The results indicate that the curvature localization zone is not suitable for the prediction of plastic hinge length in reinforced concrete deep beams. Based on the results it can be stated that in simply supported normal beams the concrete crushing zone is focused on the middle span, but in simply supported deep beams by creating a compression strut between loading place and support, the concrete crushing zone spreads along the compression trajectory. The rebar yielding zone of simply supported beams increases as the loading type is changed from the concentrated load at the middle to the uniformly distributed load.

Facilities built in areas affected by earthquake activity, such as tunnels, which have always been an integral part of human life, must withstand both dynamic and static loading. It has led to the need for practical studies on the effects of earthquakes on underground structures and the factors affecting their destruction. For this purpose, in this research, at first different patterns of tunnel’s excavation were investigated and by using Plaxis 2D software and based on Tabas earthquake in Iran, sensitivity analysis on geotechnical parameters of the soil surrounding tunnel such as cohesion, friction angle, unit weight and modulus of elasticity was carried out, and the parameters whose changes have the greatest and least effects on the bending moment changes on the tunnel lining are introduced. The results show that tunnel excavation patterns significantly affect the bending moment, axial forces, displacements, and surface settlement of the tunnel. Often, by dividing tunnel excavation area to small parts, the values of bending moment, axial forces, displacements, and surface settlement of the tunnel decreases in static analysis. Also, outputs of sensitivity analysis on geotechnical parameters of the soil surrounding tunnel showed that modulus of elasticity of the soil surrounding tunnel has the most effect and cohesion changes have the least effect on bending moment induced on tunnel lining..

In this paper, recommended spiral passive micromixer was designed and simulated. spiral design has the potential to create and strengthen the centrifugal force and the secondary flow. A series of simulations were carried out to evaluate the effects of channel width, channel depth, the gap between loops, and flowrate on the micromixer performance. These features impact the contact area of the two fluids and ultimately lead to an increment in the quality of the mixture. In this study, for the flow rate of 25 μl/min and molecular diffusion coefficient of 1×10-10 m2/s, mixing efficiency of more than 90% is achieved after 30 (approximately one-third of the total channel length). Finally, the optimized design fabricated using proposed 3D printing method.

In the present study, the nonlinear model of non-Newtonian blood flow in cosine-shape stenosed elastic artery is Numerically examined. The model is carried out for axisymmetric, two-dimensional and fully developed blood flow. The vessel wall is assumed to be have time-dependent radius that is important factor for study of blood flow. The cosine-shape stenosis convert to rigid artery by using a appropriate coordinate transformation and closed form solutions are discovered. The Sisko non-Newtonian fluid model is used for discribing blood rheology. The Navier-stokes equations of momentom containing pulastic pressure gradient. The resulting explicit of the governing nonlinear equations have been obtained Numerically with the help of the finite differece scheme and Matlab program. The key dynamic parametrs similar resistance impedance, velocity profiles and the volumetric flow rate are studied. The influence of non-Newtonian rheological properties of unsteady blood flow and stenosis severity are found and computer modeling and simulation shown graphically.

The user interface design is one of the parameters that identify the efficiency of softwares. Experiences indicate that users prefer to use softwares with limited and integrated capabilities rather than comprehensive software. In this case, this paper presents the foundational guidelines on the basis of the technical options in the forms (e.g. accessibility, language setting, etc.) that are applicable to all kinds of software environments from desktop to web-based and embedded softwares. We expect this new aspect to be useful for designers to produce friendlier and more acceptable interfaces.

In turbine practice engineering, draft tube downstream running under extreme water flow pressure and velocity. This is causing a vibrations and pressure variation during different operation frequencies. The practical challenge of obtaining a stabilized water flow is ongoing domain of research. In this paper, a proposition of initiating submerged weir in the downstream of draft tube reaction turbine is inspected. The main goal of this research is to reduce the water flow pressure variation, velocity and shear distribution in accordance to the upstream water level influence. Two types of turbines including vertical Kaplan and Francis turbine units are examined. ANSYS CFX software tool is used to build three-dimension (3D) Numerical models for the Kaplan and Francis turbines with building a submerged weir at the outlet of the draft tubes at three deferent height suggestions. The influence of the proposed submerged weir is studied the flow through these turbines by considering the dimensions of their components including the penstock with inlets, spiral casing, shafts and blades, and the draft tube with outlets. The findings of this research were tremendous proposition to solve the problem of negative pressure pulsation in draft tube of Kaplan and Francis turbines types.

In this research, in order to investigate the effect of the piezoelectric patch which is used as a sensor or actuator in rotating flexible structures such as a helicopter blade, the free vibrations of the rotating rectangular sheet with and without the piezoelectric patch have been presented. First-order shear deformation theory is considered for plate displacement and piezoelectric field. Considering the effect of Coriolis acceleration, centrifugal acceleration and centrifugal in-plane forces, the equations of motion are derived from Hamilton's principle and the electromechanical couple equation is obtained from Maxwell's equation. For piezoelectric, two electrical conditions, open circuit and closed circuit, which are used in sensors and actuators, respectively, have been considered. The equations are discretized with the help of the Numerical method of generalized differential squares and the matrices of inertia mass, eccentricity, Coriolis and stiffness matrix are obtained. Natural frequency values for beam and rotating plate have been compared in Abaqus software. Also, the values obtained from the Numerical solution in MATLAB have been verified with articles and ABAQUS, which have high accuracy. The effect of parameters such as hub radius, rotation speed, sheet thickness, aspect ratio, piezoelectric patch thickness and applied voltage on the natural frequency of the system has also been investigated.

This study is focused on the propagation of plane harmonic body waves in a transversely isotropic linear poroelastic uid-saturated medium in the framework of the simpli ed u-p formulation. A set of two scalar potential functions is employed to decouple the coupled uid continuity equation and equations of motion, such a way that the governing equations for the potential functions are resulted in the form of either scaled wave motion or a combination of repeated wave motion and transport equation. The velocities and corresponding attenuation coe cients of both longitudinal and transverse waves are extracted from the acoustic equations for the body waves. To show the validity of the analytical solution developed in this paper, the degeneration to the case of a singlephase transversely isotropic, and consequently isotropic solid is presented. The motivation behind this was to provide the possibility of comparing the results of this study and the developed solution with those reported in the literature. Besides, the e ects of mechanical and hydraulic parameters of materials on the velocity of propagation and attenuation coe cient of the waves are investigated in more detail. To this end, various synthetic poroelastic transversely isotropic materials are de ned, and the dependency of wave motion to these parameters is illustrated by plotting the graphs.