ansys

Structures with large opening roofs are vulnerable to wind, in these structures due to the low dead load, the wind load has a greater effect on these types of structures. In the calculation of wind force, one of the coefficients related to the geometry of the structure is the pressure coefficient (Cp), which is provided for some common structures in the loading regulations. Arch opening of 0.1, 0.2 and 0.3 was done using wind tunnel test and numerical modeling based on Computational Fluid Dynamics (CFD) method using ANSYS software and wind pressure coefficients on these structures are presented, it can be seen that with increasing The ratio of the height to the opening of the arch of the maximum coefficients of negative wind pressure (suction), increased in such a way that on the middle axis of the structure in the state of α = 90o, the maximum negative pressure in the structure S-1, S-2, 3-S, is equal to -2 and It is -1.7 and -1.6. The pressure coefficients on the sides facing the wind show a positive number, which indicates the pressure on these surfaces, the maximum positive pressure occurs at α=90o (the state where the direction of the wind is perpendicular to the shed) and in this case the pressure coefficient is equal to +1. In structure S-1 (height-to-opening ratio 0.3), the maximum deformation created for the wind application angle is α=40o, which is 20% more than α=90 o.

Investigation of seismic behavior and seismic safety evaluation of concrete dams has been the focus of many researchers due to the importance of dam safety during an earthquake. Because the destruction of these structures due to an earthquake can have negative economic and social effects. In the present study, the nonlinear dynamic analysis of gravity concrete dams has been done considering the effect of dam-reservoir interaction. In fact, the minimum and maximum principal stresses for the U-shaped dam and reservoir have been measured via ANSYS. Also, the present study seeks to investigate the evaluation of V-shaped dams in seismic conditions. The results show that the static analysis with non-linear behavior in the rock mass with medium and weak layers has more stability compared to the weak homogeneous system. But it is more possible to concentrate plastic strains in weak layers. Other results of this study showed that the compressive stresses in the safety check of the dam were not critical and the maximum tensile arc stresses were obtained mainly in the upper levels of the middle blocks and also in the vicinity of the contact surface with the side supports.

In the present paper, electromechanical finite element modelling of a smart adaptive composite beam is presented. The model is formulated based on linear electromechanics and electrokinematics assumptions. The proposed model is a three layers piezoelectric composite beam that acts as transversely actuator. elastic material of core is isotropic whereas the outer piezoelectric layers is orthotropic. The accuracy of analytic and numerical models is demonstrated by examining the simulation of the two principles of mechanical and electrical energy conservation in a finite element program and also comparing its results with the ANSYS numerical model. In the numerical simulation of the finite element model, there are three mesh including 10, 50, and 100 elements. Parametric simulation consists of three mechanical, electrical and electromechanical static loading sets. By comparing the results of modeling in the finite element programming and ANSYS, and verifying the principle of electromechanical energy conservation, it can be concluded that the proposed finite element model is efficiently and accurately.

Population growth, space limitation, economic and social factors are some of the reasons that led to the construction of tall buildings. However, the invention of light weight and durable materials has made tall buildings with low damping and high vibration period and sensitive to wind forces. Therefore, the study and analysis of tall buildings under wind forces seem necessary. The purpose of the present research work is to provide the necessary solutions for performance based design of a tall building having elliptic plan shape against the wind. In the present study, a tall elliptical building is exposed to wind interaction. Moreover, wind modeling and building specifications are performed in ANSYS.17 software. To simulate the atmospheric boundary layer in the software as a virtual wind tunnel, two parameters of the mean wind speed and turbulence includes length and intensity, are required. The results of software analysis were presented as a time history of longitudinal and transverse acceleration at three different heights of the building for four various mean wind speeds in short afterbody orientation for perpendicular to wind direction and 72 m/s in wind direction, then the standard deviation of acceleration was calculated and placed in standard curves of the regulation and interpreted. The effect of different factors on the performance of tall buildings against the wind is a type of response (alongwind or acrosswind), mean wind speed, orientation of the building, and the height of the desired point from the ground. Results show that the acrosswind response of tall buildings to wind does not follow a specific law and is a function of the mean wind speed, height of the building, and the alongwind and acrosswind response of the building ,i.e, displacement and accelerations .

One of the aims of structural engineers is to improve the behavior of structures and reducing their responses under dynamic lateral loads. The structural control systems are advanced techniques to reduce the structural responses against vibration, and Tuned Liquid Damper (TLD) is a well-established tool for the control of structures. In this study, the effect and behavior of TLD under 7 far-field earthquakes and 7 near-field earthquakes was investigated in ANSYS software. To assess the performance of TLD on the control of structural responses including displacement, acceleration, and velocity, the effect of four different design parameters i.e., tank length, water height, water ratio, and mass ratio (with 27 different designed alternatives based on closed-form relationships proposed in the literature) were studied. The results showed that when the water ratio and the mass ratio of the cubical container are equal to 0.375 and 5 percent respectively, The TLD had the best performance under near-fault records. Also, the designed TLD with a 5 percent mass ratio and 0.125 water ratio outperforms other designed alternatives under far-fault records. In general, and among the considered alternatives, the performance of the damper with a higher mass ratio improves all studied performance criteria. Also, the well-designed TLD could reduce the acceleration better than velocity, and velocity better than displacement.

This paper describes a numerical method for the full-range analysis of prestressed concrete flexural beams strengthened with prestressed glass fiber-reinforced polymper (GFRP) sheets, focusing on ductility and flexural strength behaviour. Prestressing concrete structures cause increased flexural strength of these structures thus increased resistance of structures, increased span length, and reduced displacements of beams are resulted, which is very effective and economically feasible. The study of ductility of these structures that have been used a lot nowadays, has a great importance because it expresses the capability of structure in inelastic deformations before destruction of members. Present paper attempts to investigate the effect of prestressed GFRP sheets on ductility and deformation of beams strengthened by this method. Regarding to this, the modelling of three sample of beams in different conditions was studied using finite element software ANSYS. After comparing the results of numerical analysis of concrete beam with GFRP sheet and the numerical results of two types of prestressed concrete beam with wire and proofing the efficiency of presented model, the displacement and energy ductility index, deformation, resistance and the amount of displacement of concrete beams have been investigated. Three beams with 160mm*280mm*3600mm dimensions have been modelled. In summary, the results express that the application of prestressed GFRP sheet may cause the least displacements of beam and an increase of 10% and 10.4% will be achieved in the flexural stiffness and ductility.

Water tanks are among the main components of water supply networks for storing, maintaining and supplying pressure, and these structures should have the ability to exploit and supply pressure in the water supply network after the earthquake. In this paper, the effect of foundation concrete hardness to tank concrete hardness on seismic analysis of air tanks has been investigated. In the current seismic analysis, the relationship between the concrete hardness of the foundation and the concrete of the tank body is expressed by the definition of the constant coefficient K. By changing this coefficient, its effect on each of the tensile/compressive stress, and displacement parameters using a probabilistic analysis is examined. The tank is modeled using a three-dimensional finite element method based on ANSYS software. In this model, the interaction between the tank body, fluid and foundation are considered and the accelerogram of Manjil earthquake in the intended model is used to apply the earthquake. The probabilistic analysis used in this study is Monte Carlo simulator using the Latin hypercube sampling method and K coefficient is used as an input variable. The maximum horizontal displacement of the structure, the maximum 1st principle stress and the maximum 3rd principle stress are selected as critical responses and output variables. The results of analyzing models and comparing responses such as maximum principle stresses and maximum displacement show that with regard to economic considerations and the appropriate reliability coefficient for the system, the most efficient and optimal value for the coefficient K is approximately 0.7.

Few studies are made about the effect of environmental conditions on the leakage flow rate. Some of these researches show that environmental conditions play an important role in leakage flow rate. On the contrary, there are other researches opposing this idea. The purpose of this research is to investigate evidence of the effect of environmental conditions on leakage flow rate. Based on this idea, some tests were carried out in the college of engineering at the university of Tehran, using a circular experimental set up at high pressure discharging to the atmosphere. Various ranges of pressure up to 50 m of water were imposed on a 110 mm diameter aged steel pipe with some holes on the pipe surface. In the next step, by using the experimental results, an analytical model in ANSYS software was developed and outputs were compared with experimental data. Later a proper mathematical turbulent model was derived. Furthermore, the effect of submerged conditions was investigated by this appropriate numerical model. The results of this research showed that static pressure fluctuations in submerged jet had significant effect on discharge and the rate of leakage was reduced in comparison with atmospheric discharge. According to the results, pressure reduction in 5 m head pressure could affect the leakage discharge under submerged condition up to 55 percent when compared with the case of discharging to the atmosphere. With pressures above 20 m, smaller changes were observed. These changes were limited to less than 10 percent. The aforementioned reduction depended on the imposed head of water at leakage point and pressure value inside the pipe. Finally, a relationship between leakage outflow and internal pressure of pipe was proposed.

1. One of the ways of controlling floods and deviating a part of the flow in open channels is to use intakes. Identifying the flow model and calculating the passing discharge are amongst the crucial issues of hydraulics engineering. Using flow meters is one of the most popular methods of measuring the velocity or the discharge in open channels. Flowmeters rely on measuring the velocity and they calculate the discharge through the continuity equation as the multiplication of the mean velocity by the wet cross section (Q = A(h ×Umean). The A (h) cross section is computed through measuring the height of the free surface (h) and using precise geometrical information. Determining the mean velocity passing through the cross section requires special knowledge. It should be noted that due to the three-dimensional and complex nature of the flow near the intake location and the presence of strong secondary flows in the transverse cross section, the velocity measured by the sensors located on the flowmeter in the intended area is different from the actual mean velocity of the channel. However, despite this difference, the mean velocities measured by the flowmeter are fairly consistent with the actual mean velocity area of the channel. The velocity of the passing flows and the geometrical size of the main and branch channels affect the difference between the velocity measured by the flowmeter and the actual mean velocity of the flow [1-6].2. The experimental model [7] of a 90-degree intake with a rectangular cross section has been three dimensionally simulated by the ANSYS- CFX software in this study. The k-ω turbulence model has been used to solve the turbulence equations in this simulation. The results of the numerical model have been compared with that of the experimental model in order to examine the accuracy of the numerical model. The flowmeter measurement accuracy was examined in different width ratios wr= 1.4, 1.2, 1.0, 0.8, 0.6 (the branch channel width to the main channel width) through using the numerical model and the results of the experimental model after verification. With regard to the fact that the discharge passing through the branch channel is constant in all the wr states, the effective ratio for fluid movement increases in the branch channel as the width ratio increases as the result of an increase in the branch channel width from wr= 0.6 to wr= 1.4. This causes the width of the separation zone and the contraction degree of the compression zone to increase and the longitudinal velocity to get close to v*max equal to -0.6. Therefore wr= 1.4 width ratio is considered the critical width ratio among all the presented wrs regarding the vastness and density of the separation zone and the compression zone. An increase in the width ratio of the channels increase the difference between the read velocities and the mean velocity of the branch channel which means as the width ratio increases from wr= 0.6 to wr=1.0, the difference between the read velocity and the branch channel mean velocity increases from 18 percent to 139 percent at the peak point. The reason behind this error percentage increase is that as wr= 0.6 increases to wr= 1.0, the size of the separation zone increases and the density of the contraction zone increases as well however this increasing process continues to wr= 1.0, width ratio and after the width ratio of 1 as the width ratio of the channels increase from wr= 1.0 to wr= 1.4, the difference between the read velocities and the actual mean velocity decreases in the branch channel which means as the width ratio increases from wr= 1.0 to wr= 1.4, the difference between the read velocity and the branch channel mean velocity drops from 139 percent to 47 percent because as the width ratio increases from wr= 1.0 to wr= 1.4, the effective ratio of fluid movement increases in the channel and the difference between the read velocity and the branch channel mean velocity increases. This is because when the channels’ width ratios become excessively large, the branch channel’s cross section excessively increases and as a result the flow velocity significantly drops and this decreases in the velocity leads to lesser volume of flow entering the separation zone and the value of vmax decreases in the compression zone and so the difference between the read longitudinal velocity and the branch channel mean velocity decreases.4. With regard to the results, the flowmeter measurement accuracy is fairly desirable in the middle of the channel in specific longitudinal distances except for the rotating areas. In case the flowmeters are installed exactly in the complex rotation areas and the deviation location their measurement accuracy decreases and the maximum error is equal to 139 percent in some cross sections and this error percentage occurs in wr= 1.0 width ratio (Fig. 1). In other words when the branch channel width is equal to the main channel width, the difference between the velocity read by the flowmeter and the branch channel mean velocity reaches its maximum level.

I‌n t‌h‌i‌s p‌a‌p‌e‌r, s‌o‌m‌e m‌a‌t‌e‌r‌i‌a‌l a‌n‌d g‌e‌o‌m‌e‌t‌r‌i‌c‌a‌l n‌o‌n‌l‌i‌n‌e‌a‌r e‌f‌f‌e‌c‌t‌s, a‌n‌d m‌e‌t‌h‌o‌d‌s o‌f s‌e‌c‌o‌n‌d o‌r‌d‌e‌r n‌o‌n‌l‌i‌n‌e‌a‌r a‌d‌v‌a‌n‌c‌e‌d a‌n‌a‌l‌y‌s‌i‌s a‌r‌e i‌n‌v‌e‌s‌t‌i‌g‌a‌t‌e‌d. N‌u‌m‌e‌r‌i‌c‌a‌l m‌e‌t‌h‌o‌d‌s a‌r‌e u‌s‌e‌d t‌o i‌n‌v‌e‌s‌t‌i‌g‌a‌t‌e t‌h‌e e‌f‌f‌e‌c‌t o‌f r‌e‌p‌l‌a‌c‌i‌n‌g c‌o‌n‌c‌e‌n‌t‌r‌i‌c b‌r‌a‌c‌e‌s o‌n s‌t‌e‌e‌l f‌r‌a‌m‌e p‌e‌r‌f‌o‌r‌m‌a‌n‌c‌e. T‌h‌r‌e‌e, s‌i‌x, t‌e‌n a‌n‌d t‌w‌e‌n‌t‌y s‌t‌o‌r‌y 2D f‌r‌a‌m‌e‌s w‌i‌t‌h e‌i‌g‌h‌t d‌i‌f‌f‌e‌r‌e‌n‌t a‌r‌r‌a‌y‌s o‌f b‌r‌a‌c‌e‌s a‌n‌d f‌o‌u‌r l‌o‌a‌d‌i‌n‌g‌s a‌r‌e a‌n‌a‌l‌y‌z‌e‌d. A‌N‌S‌Y‌S f‌i‌n‌i‌t‌e e‌l‌e‌m‌e‌n‌t s‌o‌f‌t‌w‌a‌r‌e w‌a‌s u‌t‌i‌l‌i‌z‌e‌d t‌o p‌e‌r‌f‌o‌r‌m s‌e‌c‌o‌n‌d o‌r‌d‌e‌r n‌o‌n‌l‌i‌n‌e‌a‌r a‌n‌a‌l‌y‌s‌i‌s a‌n‌d L‌a‌t‌e‌r‌a‌l L‌o‌a‌d-D‌i‌s‌p‌l‌a‌c‌e‌m‌e‌n‌t c‌u‌r‌v‌e‌s w‌e‌r‌e d‌r‌a‌w‌n. C‌u‌r‌v‌e‌s l‌i‌n‌e‌a‌r r‌e‌g‌r‌e‌s‌s‌i‌o‌n w‌a‌s c‌a‌l‌c‌u‌l‌a‌t‌e‌d t‌o d‌e‌f‌i‌n‌e n‌e‌w l‌a‌t‌e‌r‌a‌l s‌t‌i‌f‌f‌n‌e‌s‌s s‌h‌o‌w‌i‌n‌g t‌h‌e f‌r‌a‌m‌e‌s p‌e‌r‌f‌o‌r‌m‌a‌n‌c‌e. T‌h‌e m‌e‌t‌h‌o‌d u‌s‌e‌d i‌n t‌h‌i‌s i‌n‌v‌e‌s‌t‌i‌g‌a‌t‌i‌o‌n i‌s p‌l‌a‌s‌t‌i‌c r‌e‌g‌i‌o‌n s‌e‌c‌o‌n‌d-o‌r‌d‌e‌r n‌o‌n‌l‌i‌n‌e‌a‌r a‌n‌a‌l‌y‌s‌i‌s a‌n‌d i‌s a‌p‌p‌l‌i‌e‌d t‌o s‌t‌r‌u‌c‌t‌u‌r‌a‌l s‌y‌s‌t‌e‌m a‌n‌a‌l‌y‌s‌i‌s, b‌a‌s‌e‌d o‌n t‌h‌e m‌o‌d‌i‌f‌i‌e‌d f‌i‌n‌i‌t‌e e‌l‌e‌m‌e‌n‌t m‌e‌t‌h‌o‌d. T‌h‌e p‌l‌a‌s‌t‌i‌c-e‌l‌a‌s‌t‌i‌c h‌i‌n‌g‌e m‌o‌d‌e‌l r‌e‌f‌e‌r‌s t‌o t‌h‌e s‌i‌m‌p‌l‌e‌s‌t a‌n‌a‌l‌y‌s‌i‌s. B‌y c‌o‌m‌p‌a‌r‌i‌s‌o‌n, t‌h‌e p‌l‌a‌s‌t‌i‌c-e‌l‌a‌s‌t‌i‌c r‌e‌g‌i‌o‌n m‌o‌d‌e‌l i‌l‌l‌u‌s‌t‌r‌a‌t‌e‌s t‌h‌e m‌o‌s‌t r‌e‌f‌o‌r‌m‌a‌t‌i‌o‌n‌s. T‌h‌e p‌l‌a‌s‌t‌i‌c r‌e‌g‌i‌o‌n a‌n‌a‌l‌y‌s‌i‌s m‌e‌t‌h‌o‌d m‌o‌d‌e‌l‌s p‌l‌a‌s‌t‌i‌c d‌e‌v‌e‌l‌o‌p‌m‌e‌n‌t i‌n t‌h‌e w‌h‌o‌l‌e s‌t‌r‌u‌c‌t‌u‌r‌e. T‌h‌i‌s m‌e‌t‌h‌o‌d i‌s p‌e‌r‌f‌o‌r‌m‌e‌d i‌n t‌w‌o w‌a‌y‌s. T‌h‌e f‌i‌r‌s‌t o‌n‌e i‌s l‌a‌t‌t‌i‌c‌e, u‌s‌i‌n‌g f‌i‌n‌i‌t‌e e‌l‌e‌m‌e‌n‌t, a‌n‌d t‌h‌e s‌e‌c‌o‌n‌d i‌s b‌a‌s‌e‌d o‌n t‌h‌e B‌e‌a‌m-C‌o‌l‌u‌m‌n t‌h‌e‌o‌r‌y. T‌h‌e s‌e‌c‌o‌n‌d o‌r‌d‌e‌r n‌o‌n‌l‌i‌n‌e‌a‌r a‌n‌a‌l‌y‌s‌i‌s u‌s‌e‌d i‌n t‌h‌i‌s p‌a‌p‌e‌r e‌n‌u‌m‌e‌r‌a‌t‌e‌d p‌l‌a‌s‌t‌i‌c r‌e‌g‌i‌o‌n a‌d‌v‌a‌n‌c‌e‌d a‌n‌a‌l‌y‌s‌i‌s, a‌n‌d i‌n‌c‌l‌u‌d‌e‌s n‌o‌n‌l‌i‌n‌e‌a‌r‌i‌t‌y i‌n g‌e‌o‌m‌e‌t‌r‌y a‌n‌d m‌a‌t‌e‌r‌i‌a‌l, l‌i‌k‌e s‌e‌c‌o‌n‌d o‌r‌d‌e‌r e‌f‌f‌e‌c‌t‌s (P-$\p‌o‌u‌n‌d‌s$ a‌n‌d P-$\D‌e‌l‌t‌a$), r‌e‌d‌i‌s‌t‌r‌i‌b‌u‌t‌i‌o‌n o‌f i‌n‌t‌e‌r‌n‌a‌l l‌o‌a‌d‌s, b‌e‌c‌a‌u‌s‌e o‌f p‌l‌a‌s‌t‌i‌c r‌e‌g‌i‌o‌n f‌o‌r‌m‌a‌t‌i‌o‌n, l‌a‌t‌e‌r‌a‌l s‌t‌i‌f‌f‌n‌e‌s‌s d‌e‌g‌r‌a‌d‌a‌t‌i‌o‌n, b‌a‌s‌e‌d o‌n s‌t‌e‌e‌l y‌i‌e‌l‌d‌i‌n‌g, a‌n‌d s‌h‌e‌a‌r d‌e‌f‌o‌r‌m‌a‌t‌i‌o‌n‌s. T‌o a‌p‌p‌l‌y a‌l‌l t‌h‌e m‌e‌n‌t‌i‌o‌n‌e‌d f‌a‌c‌t‌o‌r‌s i‌n t‌h‌e a‌n‌a‌l‌y‌s‌i‌s, m‌a‌n‌y m‌e‌t‌h‌o‌d‌s a‌n‌d c‌o‌d‌e‌s w‌e‌r‌e s‌u‌g‌g‌e‌s‌t‌e‌d b‌y o‌t‌h‌e‌r a‌u‌t‌h‌o‌r‌s. F‌o‌r e‌x‌a‌m‌p‌l‌e, t‌h‌e A‌I‌S‌C-L‌R‌F‌D c‌o‌d‌e a‌p‌p‌l‌i‌e‌s a‌n e‌f‌f‌e‌c‌t‌i‌v‌e l‌e‌n‌g‌t‌h f‌a‌c‌t‌o‌r, e‌n‌h‌a‌n‌c‌e‌m‌e‌n‌t f‌a‌c‌t‌o‌r a‌n‌d i‌n‌t‌e‌r‌a‌c‌t‌i‌o‌n d‌e‌s‌i‌g‌n t‌e‌r‌m o‌f t‌h‌e m‌e‌n‌t‌i‌o‌n‌e‌d f‌a‌c‌t‌o‌r‌s i‌n a‌n‌a‌l‌y‌s‌i‌s a‌n‌d d‌e‌s‌i‌g‌n. T‌h‌e r‌e‌a‌s‌o‌n i‌s b‌e‌c‌a‌u‌s‌e o‌f t‌h‌e l‌o‌w q‌u‌a‌l‌i‌t‌y o‌f c‌o‌m‌p‌u‌t‌e‌r‌s w‌h‌e‌n c‌o‌d‌e‌s w‌e‌r‌e o‌r‌i‌g‌i‌n‌a‌l‌l‌y e‌s‌t‌a‌b‌l‌i‌s‌h‌e‌d. S‌e‌c‌o‌n‌d o‌r‌d‌e‌r n‌o‌n‌l‌i‌n‌e‌a‌r a‌d‌v‌a‌n‌c‌e‌d a‌n‌a‌l‌y‌s‌i‌s c‌o‌u‌l‌d a‌p‌p‌l‌y a‌l‌l t‌h‌e m‌e‌n‌t‌i‌o‌n‌e‌d t‌e‌r‌m‌s i‌n t‌h‌e d‌e‌s‌i‌g‌n p‌r‌o‌c‌e‌d‌u‌r‌e d‌i‌r‌e‌c‌t‌l‌y. T‌h‌i‌s m‌e‌t‌h‌o‌d a‌s‌s‌i‌m‌i‌l‌a‌t‌e‌s a‌n‌a‌l‌y‌s‌i‌s a‌n‌d d‌e‌s‌i‌g‌n, s‌o, d‌e‌s‌i‌g‌n‌e‌r‌s d‌o n‌o‌t n‌e‌e‌d d‌i‌f‌f‌e‌r‌e‌n‌t c‌o‌d‌e‌s. I‌t i‌s h‌o‌p‌e‌d t‌h‌a‌t t‌h‌e‌s‌e m‌e‌t‌h‌o‌d‌s w‌i‌l‌l b‌e u‌s‌e‌d a‌s a c‌o‌m‌m‌o‌n s‌t‌r‌u‌c‌t‌u‌r‌a‌l a‌n‌a‌l‌y‌s‌i‌s/d‌e‌s‌i‌g‌n m‌e‌t‌h‌o‌d b‌y d‌e‌v‌e‌l‌o‌p‌i‌n‌g c‌o‌m‌p‌u‌t‌e‌r‌s. E‌a‌c‌h a‌n‌a‌l‌y‌s‌i‌s t‌h‌a‌t c‌o‌u‌l‌d d‌e‌t‌e‌r‌m‌i‌n‌e t‌h‌e s‌t‌r‌e‌n‌g‌t‌h a‌n‌d s‌t‌a‌b‌i‌l‌i‌t‌y o‌f s‌t‌r‌u‌c‌t‌u‌r‌a‌l s‌y‌s‌t‌e‌m‌s a‌n‌d i‌s‌o‌l‌a‌t‌e‌d m‌e‌m‌b‌e‌r‌s i‌n s‌u‌c‌h a w‌a‌y t‌h‌a‌t d‌o‌e‌s n‌o‌t n‌e‌e‌d t‌o c‌o‌n‌t‌r‌o‌l i‌s‌o‌l‌a‌t‌e‌d m‌e‌m‌b‌e‌r‌s c‌a‌p‌a‌c‌i‌t‌y a‌n‌d t‌h‌e d‌e‌f‌i‌n‌i‌t‌i‌o‌n o‌f e‌f‌f‌e‌c‌t‌i‌v‌e l‌e‌n‌g‌t‌h c‌o‌e‌f‌f‌i‌c‌i‌e‌n‌t i‌s e‌n‌u‌m‌e‌r‌a‌t‌e‌d a‌s a‌d‌v‌a‌n‌c‌e‌d a‌n‌a‌l‌y‌s‌i‌s. T‌h‌i‌s m‌e‌t‌h‌o‌d g‌i‌v‌e‌s m‌u‌c‌h i‌n‌f‌o‌r‌m‌a‌t‌i‌o‌n t‌o d‌e‌s‌i‌g‌n‌e‌r‌s a‌b‌o‌u‌t t‌h‌e b‌e‌h‌a‌v‌i‌o‌r o‌f s‌t‌r‌u‌c‌t‌u‌r‌e‌s e‌x‌p‌o‌s‌e‌d t‌o e‌x‌t‌e‌r‌n‌a‌l l‌o‌a‌d‌s a‌n‌d e‌n‌v‌i‌r‌o‌n‌m‌e‌n‌t‌a‌l c‌o‌n‌d‌i‌t‌i‌o‌n‌s. I‌n t‌h‌i‌s i‌n‌v‌e‌s‌t‌i‌g‌a‌t‌i‌o‌n, a B‌E‌A‌M e‌l‌e‌m‌e‌n‌t w‌a‌s u‌t‌i‌l‌i‌z‌e‌d t‌o m‌o‌d‌e‌l s‌t‌r‌u‌c‌t‌u‌r‌e‌s. R‌e‌s‌u‌l‌t‌s s‌h‌o‌w t‌h‌a‌t a‌p‌p‌l‌y‌i‌n‌g t‌h‌e m‌e‌t‌h‌o‌d u‌s‌e‌d i‌n A‌N‌S‌Y‌S c‌o‌u‌l‌d d‌e‌t‌e‌r‌m‌i‌n‌e t‌h‌e f‌r‌a‌m‌e u‌l‌t‌i‌m‌a‌t‌e l‌o‌a‌d‌i‌n‌g c‌o‌e‌f‌f‌i‌c‌i‌e‌n‌t o‌f ``V‌o‌g‌e‌l F‌r‌a‌m‌e'' b‌y 3 p‌e‌r‌c‌e‌n‌t t‌o‌l‌e‌r‌a‌n‌c‌e, c‌o‌m‌p‌a‌r‌e‌d t‌o t‌h‌e p‌l‌a‌s‌t‌i‌c r‌e‌g‌i‌o‌n a‌n‌a‌l‌y‌s‌i‌s m‌e‌t‌h‌o‌d a‌n‌d p‌l‌a‌s‌t‌i‌c h‌i‌n‌g‌e a‌n‌a‌l‌y‌s‌i‌s. P‌e‌r‌f‌o‌r‌m‌i‌n‌g a‌b‌o‌u‌t e‌i‌g‌h‌t‌y a‌n‌a‌l‌y‌s‌e‌s d‌e‌n‌o‌t‌e‌d t‌h‌a‌t c‌h‌a‌n‌g‌i‌n‌g b‌r‌a‌c‌i‌n‌g a‌r‌r‌a‌y‌s c‌o‌u‌l‌d i‌n‌c‌r‌e‌a‌s‌e o‌r d‌e‌c‌r‌e‌a‌s‌e u‌l‌t‌i‌m‌a‌t‌e s‌t‌r‌e‌n‌g‌t‌h, u‌l‌t‌i‌m‌a‌t‌e d‌i‌s‌p‌l‌a‌c‌e‌m‌e‌n‌t a‌n‌d l‌a‌t‌e‌r‌a‌l s‌t‌i‌f‌f‌n‌e‌s‌s m‌u‌l‌t‌i‌p‌l‌e t‌i‌m‌e‌s. T‌o i‌n‌c‌r‌e‌a‌s‌e t‌h‌e u‌l‌t‌i‌m‌a‌t‌e s‌t‌r‌e‌n‌g‌t‌h c‌o‌e‌f‌f‌i‌c‌i‌e‌n‌t, t‌h‌e b‌e‌s‌t o‌p‌t‌i‌o‌n i‌s u‌s‌i‌n‌g a‌n X-b‌r‌a‌c‌e f‌r‌a‌m‌e. F‌u‌r‌t‌h‌e‌r‌m‌o‌r‌e, a‌p‌p‌l‌y‌i‌n‌g d‌i‌a‌g‌o‌n‌a‌l b‌r‌a‌c‌i‌n‌g i‌n o‌f‌f s‌i‌d‌e s‌p‌a‌n‌s c‌o‌u‌l‌d d‌e‌c‌l‌i‌n‌e t‌h‌e l‌a‌t‌e‌r‌a‌l d‌i‌s‌p‌l‌a‌c‌e‌m‌e‌n‌t o‌f t‌h‌e s‌t‌r‌u‌c‌t‌u‌r‌e. F‌r‌a‌m‌e‌s w‌i‌t‌h‌o‌u‌t a b‌r‌a‌c‌i‌n‌g s‌y‌s‌t‌e‌m a‌n‌d w‌i‌t‌h C‌h‌e‌v‌r‌o‌n a‌n‌d e‌c‌c‌e‌n‌t‌r‌i‌c b‌r‌a‌c‌i‌n‌g s‌y‌s‌t‌e‌m‌s d‌e‌m‌o‌n‌s‌t‌r‌a‌t‌e t‌h‌e m‌o‌s‌t n‌o‌n‌l‌i‌n‌e‌a‌r‌i‌t‌y.

The application of structural arch form in Iran goes back to as far as thousands of years ago. Arch is a fundamental component of Iranian architecture. Other structural systems such as vaults and domes which are used widely in variety of structures are indeed derived from arches. In the present study, the stability of various Iranian arches versus their weight, surcharge and earthquake action is investigated. The selected arches are some of the most applied Iranian arches like: parabolic-shaped arches, onion-shaped arches, four-centered pointed arches, obtuse angel arches and basket-handle arches. The selected arches are modeled in AutoCAD software and then are exported into the ANSYS software for necessary analyses. The static analysis, modal analysis and linear and non-linear dynamic analysis have been carried out on the finite element models of the arches. Comparison of the results of the analyses showed that for the same span and thickness in various Iranian arches analyzed in the present study, the parabolic-shaped arch has a better bearing with respect to gravity and lateral loads. The static stability of the arches under the gravity load increases with rise to span ratio of the arch. The other factor that affects the arch stability is its angle of contact to the baseline. According to the two above mentioned factors the stability of the selected arches increases in the following order: the semi-elliptical arch, the parabolic-shaped arch, basket-handle arch, circular arch and four-centered pointed arch. The eigne-value analyses have shown that the natural period of the arch in sensitive to the form of the crown. For the same span, the arches with tipped crown possess larger periods. In this regard, the fundamental period for parabolic arch is the least. This shows that this type of arch is stiffer that the other ones. For dynamic analysis of the selected arches, three strong ground motions of Kobe of Japan in 1995 (ML=7.2), Tabas of Iran in 1978 (ML=7.8) and Manjil of Iran in 1990 (Mw=7.4) were selected. Again, the time history analysis of the arches shows that the strongest arch against the selected accelerograms is parabolic arch; and the order of relative seismic stability of the arches descending from high to low is as following: the parabolic-shaped arch, the basket handle arch, the four-centered pointed arch, the Semi-elliptical arch and the circular arch. Also, under the Kobe earthquake accelerogram, the parabolic arch showed no collapse. However, the other arches encountered collapse and among the circular arch collapsed at 5.8 seconds as the first arch and the basket handle arch collapsed at 8.5 as the last one. As another result, the location of cracks in the arches damaged by seismic loading was in the internal face of the arch.