Journal articles on the topic 'Wall models'
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1
Zhang, Ruifeng, and Xiaojing Wang. "On generalized geometric domain-wall models." Proceedings of the Royal Society of Edinburgh: Section A Mathematics 141, no. 4 (July 15, 2011): 881–95. http://dx.doi.org/10.1017/s0308210510001198.
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We study domain walls that are topological solitons in one dimension. We present an existence theory for the solutions of the basic governing equations of some extended geometrically constrained domain-wall models. When the cross-section and potential density are both even, we establish the existence of an odd domain-wall solution realizing the phase-transition process between two adjacent domain phases. When the cross-section satisfies a certain integrability condition, we prove that a domain-wall solution always exists that links two arbitrarily designated domain phases.
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Jiao, Jianying, and Ye Zhang. "Multiscale subgrid models of large eddy simulation for turbulent flows." International Journal of Numerical Methods for Heat & Fluid Flow 26, no. 5 (June 6, 2016): 1380–90. http://dx.doi.org/10.1108/hff-01-2015-0009.
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Purpose – The purpose of this paper is to propose three modified subgrid-scale (SGS) eddy-viscosity models to improve their original eddy-viscosity models (the Smagorinsky model (SM), the mixed-scale model (MSM), and the wall-adapted local eddy-viscosity model (WALE)) in the simulation of turbulent flows in near-wall region. Design/methodology/approach – The subgrid viscosity is related to the norm of strain rate tensor of the smallest resolved scales, instead of the norm of the resolved strain rate tensor of the large scales. Findings – All the SGS viscosity of the modified eddy-viscosity models (small-large model, modified MSM, and modified WALE) is closer to y+3 behavior than those of the original eddy-viscosity models (SM, MSM, and WALE) near the wall. Originality/value – The norm of strain rate tensor of the smallest scales used in eddy-viscosity models, instead of the norm of strain rate tensor, makes the eddy viscosity in near-wall region approach to zero in a physical sense.
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Kanvinde, Amit M., and Gregory G. Deierlein. "Analytical Models for the Seismic Performance of Gypsum Drywall Partitions." Earthquake Spectra 22, no. 2 (May 2006): 391–411. http://dx.doi.org/10.1193/1.2191927.
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Gypsum drywall partitions may contribute significantly to the lateral strength and stiffness of woodframe structures, whether or not the walls are explicitly designed for that purpose. This paper proposes analytical models to determine the lateral shear strength and initial elastic stiffness of wood-framed gypsum wall panels, taking into account the effects of wall geometry, door and window openings, connector type and spacing, and wall boundary conditions. The strength and stiffness models are incorporated in a multilinear curve to describe the monotonic lateral shear versus deformation response of the walls. Additional parameters to calibrate the response of a peak-oriented hysteretic cyclic model are also proposed, thus making the models suitable for nonlinear time-history simulations of woodframe buildings. The models are developed and validated using published data from 16 shear tests of full-scale gypsum wall panels.
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VOLKAS, RAYMOND R. "REALISTIC DOMAIN-WALL-BRANE MODELS?" Modern Physics Letters A 23, no. 17n20 (June 28, 2008): 1529–35. http://dx.doi.org/10.1142/s0217732308027928.
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Rybiński, Witold, and Jarosław Mikielewicz. "Analytical 1D models of the wall thermal resistance of rectangular minichannels applied in heat exchangers." Archives of Thermodynamics 37, no. 3 (September 1, 2016): 63–78. http://dx.doi.org/10.1515/aoter-2016-0020.
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Abstract The paper presents four 1-dimensional models of thermal resistance of walls in a heat exchanger with rectangular minichannels. The first model is the simplest one, with a single wall separating two fluids. The second model of the so called equivalent wall takes into account total volume of intermediate walls between layers of minichannels and of side walls of minichannels. The next two more complicated models take separately into account thermal resistance of these walls. In these two models side walls are treated as fins. The results of models comparison are presented. It is shown that thermal resistance may be neglected for metal walls but it should be taken into account for the walls made of plastics. For the case of non-neglected wall thermal resistance the optimum wall thickness was derived. Minichannel heat exchangers made of plastic are larger than those built of metal, but are significantly cheaper. It makes possible to use of such exchangers in inexpensive microscale ORC installations.
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Jiang, Huan Jun, and Lao Er Liu. "Numerical Analysis of RC Shear Walls under Cyclic Loading by PERFORM-3D." Advanced Materials Research 250-253 (May 2011): 2253–57. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.2253.
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For engineering practice purpose, the macroscopic model capable of simulating the main characteristics of nonlinear behavior is desirable to reduce computational efforts in nonlinear structural analysis. Several different types of macroscopic models for shear walls have been developed. The shear wall element used in the commercial program PERFORM-3D is one types of macroscopic models for reinforced concrete shear walls. The application of PERFORM-3D in the nonlinear static analysis of reinforced concrete shear walls is introduced in this study. The selection of constitutive models and the determination of related parameters of the constituent material are presented in detail. The applicability of the shear wall element is verified by numerical simulation on three reinforced concrete shear wall specimens under cyclic loading. The comparison between the numerical analysis and test results leads to the conclusion that the shear wall element with appropriate constitutive models can capture the nonlinear behavior of reinforced concrete shear wall well and be conveniently applied in engineering practice.
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BUNESCU, Ionut, Sterian DANAILA, Mihai-Victor PRICOP, and Adrian DINA. "Estimation of Wind Tunnel Corrections Using Potential Models." INCAS BULLETIN 11, no. 1 (March 5, 2019): 53–60. http://dx.doi.org/10.13111/2066-8201.2019.11.1.4.
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The evaluation of the tunnel correction remains an actual problem, especially for the effect of tunnel walls. Even if the experimental campaign meets the basic similitude criteria (Mach, Reynolds etc.), the wall effect on the measured data is always present. Consequently, the flow correction due the limited by walls must be evaluated. Solid wall corrections refer to the aerodynamic interference between the experimental model and the walls of the wind tunnel. This interaction affects the measured forces and implicitly the angle of attack. Usually, these effects are introduced through semi-empirical correction factors which change the global measured forces. The present paper refers to the mathematical and numerical modeling of aerodynamic interferences between the experimental model and the solid walls based on the potential flow model. The main goal is to asses a method allowing an estimate of the corrections for each configuration with a minimum computational resource.
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Bao, Quoc To, Kihak Lee, Sung-Jig Kim, and Jiuk Shin. "Quantifying Effect of Post-Tensioned Bars for Precast Concrete Shear Walls." Sustainability 14, no. 10 (May 18, 2022): 6141. http://dx.doi.org/10.3390/su14106141.
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A hybrid concrete wall is made up of a traditional reinforced concrete wall with post-tensioned technology. Recent research has shown that post-tensioned (PT) reinforced concrete shear walls have a wide range of advantages when it comes to resisting lateral forces and lateral moments caused by earthquake loading. To explore the PT reinforced concrete wall behavior subjected to seismic load, the concrete models were augmented with various material models, including the KCC, CDP, and Winfrith models for a PT 2D wall under pushover analysis. To ensure that the overall behavior forecast was qualitatively acceptable, the models’ performance was compared to experimental findings. Then, the post-tensioned modeling approach was implemented with the 3D wall in order to predict structural responses of the PT 3D wall. The well-validated finite element models were ultilized to estimate the effects of the post-tensioned bars on lateral resisting capacities of the precast concrete shear wall.
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Budwig, R., D. Elger, H. Hooper, and J. Slippy. "Steady Flow in Abdominal Aortic Aneurysm Models." Journal of Biomechanical Engineering 115, no. 4A (November 1, 1993): 418–23. http://dx.doi.org/10.1115/1.2895506.
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Steady flow in abdominal aortic aneurysm models has been examined for four aneurysm sizes over Reynolds numbers from 500 to 2600. The Reynolds number is based on entrance tube diameter, and the inlet condition is fully developed flow. Experimental and numerical methods have been used to determine: (i) the overall features of the flow, (ii) the stresses on the aneurysm walls in laminar flow, and (iii) the onset and characteristics of turbulent flow. The laminar flow field is characterized by a jet of fluid (passing directly through the aneurysm) surrounded by a recirculating vortex. The wall shear stress magnitude in the recirculation zone is about ten times less than in the entrance tube. Both wall shear stress and wall normal stress profiles exhibit large magnitude peaks near the reattachment point at the distal end of the aneurysm. The onset of turbulence in the model is intermittent for 2000 < Re < 2500. The results demonstrate that a slug of turbulence in the entrance tube grows much more rapidly in the aneurysm than in a corresponding length of uniform cross section pipe. When turbulence is present in the aneurysm the recirculation zone breaks down and the wall shear stress returns to a magnitude comparable to that in the entrance tube.
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Irda Mazni, Deni. "An alternative model of retaining walls on sandy area to prevent landslides." E3S Web of Conferences 156 (2020): 02016. http://dx.doi.org/10.1051/e3sconf/202015602016.
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Landslide is one of the potential disasters that can take life and material. A way to reduce disaster risk in slopes is to improve slope stability. A challenge in improving slope stability is how to make soil retaining walls that are simple, quickly built, and workable in the process. This research focuses on laboratory tests of gravity, segmental, and pre-cast retaining walls in sands. The tested models are slopes with different segmental, pre-cast, gravity walls made of un-reinforced concrete for static loads. The slope failure patterns were observed with their load variations. There are two wall models segmental. Each segmental wall observed a collapse pattern that occurred behind the wall. Static loading is carried out step by step until collapse occurs in the segmental wall. Observations and defects are carried out during the load process until the segmental wall collapses. This research shows that segmental pre-cast retaining walls with specific models and sizes can be selected to support certainly given loads to prevent slope failure.
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Cebeci, Tuncer, K. C. Chang, C. Li, and J. H. Whitelaw. "Turbulence models for wall boundary layers." AIAA Journal 24, no. 3 (March 1986): 359–60. http://dx.doi.org/10.2514/3.9274.
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Pigarov, A. Yu, P. Krstic, S. I. Krasheninnikov, R. Doerner, and T. D. Rognlien. "Dynamic Models for Plasma-Wall Interactions." Contributions to Plasma Physics 52, no. 5-6 (June 2012): 465–77. http://dx.doi.org/10.1002/ctpp.201210035.
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Gómez Bernal, Alonso, Daniel A. Manzanares-Ponce, Omar Vargas-Arguello, Eduardo Arellano-Méndez, Hugón Juárez-García, and Oscar M. González-Cuevas. "Experimental behavior of a masonry wall supported on a RC twoway slab." DYNA 82, no. 194 (December 21, 2015): 96–103. http://dx.doi.org/10.15446/dyna.v82n194.46333.
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This paper discusses the experimental results of a prototype slab-wall that is subjected to vertical and horizontal cyclic loading. The key aspects under discussion are: (a) the differences between the capacity resistance of a wall supported on a slab vs. a wall supported on a fixed base, (b) the implications when shear walls are placed directly on transfer concrete slabs, and (c) the effects that these walls cause on the slabs. The most important results presented herein are the change on lateral stiffness and resistance capacity of the load-bearing wall supported on a slab versus the wall supported on a fixed base. Analytical finite element slab-wall models were built using ANSYS. During the experimental test process of horizontal loading, we detected that the stiffness of the slab-wall system decreased by a third compared to the one on the fixed base wall; a result that supported by the numerical models.
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Yi, Junyi, and Nigel G. Shrive. "Behaviour of hollow concrete masonry walls with one-course bond beams subjected to concentric and eccentric concentrated loading." Canadian Journal of Civil Engineering 30, no. 1 (February 1, 2003): 181–90. http://dx.doi.org/10.1139/l02-102.
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Three-dimensional finite element models of unreinforced hollow concrete masonry walls with one-course bond beams subjected to concentrated loading have been analyzed. The walls were modelled with different loading plate sizes, different loading locations along the wall (at the midpoint of the wall, at the end of the wall, and between these points), and different out-of-plane eccentricities (e = 0, t/6, and t/3). The hollow block units, mortar, grout, and bond beam blocks in the walls were modelled separately. Both smeared and discrete cracking methods have been utilized for predicting cracking under load. Geometric and material nonlinearities and damage due to progressive cracking were taken into account in the analyses. The predicted failure modes and ultimate capacities of the walls with the concentric concentrated load applied at the midpoint or at the end of the wall compared very well with the experimental results. When the load was between the midpoint and the end of the wall, the predicted ultimate capacity was between those for the load at the midpoint and at the end. The strength of the walls decreases with increasing out-of-plane eccentricities.Key words: finite element models, hollow masonry, smeared and discrete cracking models, concentrated load, loading locations, out-of-plane eccentricities.
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Keerthan, Poologanathan, and Mahen Mahendran. "Thermal Performance of Load Bearing Cold-formed Steel Walls under Fire Conditions using Numerical Studies." Journal of Structural Fire Engineering 5, no. 3 (August 19, 2014): 261–90. http://dx.doi.org/10.1260/2040-2317.5.3.261.
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Cold-formed Light gauge Steel Frame (LSF) wall systems are increasingly used in low-rise and multi-storey buildings and hence their fire safety has become important in the design of buildings. A composite LSF wall panel system was developed recently, where a thin insulation was sandwiched between two plasterboards to improve the fire performance of LSF walls. Many experimental and numerical studies have been undertaken to investigate the fire performance of non-load bearing LSF wall under standard conditions. However, only limited research has been undertaken to investigate the fire performance of load bearing LSF walls under standard and realistic design fire conditions. Therefore in this research, finite element thermal models of both the conventional load bearing LSF wall panels with cavity insulation and the innovative LSF composite wall panel were developed to simulate their thermal behaviour under standard and realistic design fire conditions. Suitable thermal properties were proposed for plasterboards and insulations based on laboratory tests and available literature. The developed models were then validated by comparing their results with available fire test results of load bearing LSF wall. This paper presents the details of the developed finite element models of load bearing LSF wall panels and the thermal analysis results. It shows that finite element models can be used to simulate the thermal behaviour of load bearing LSF walls with varying configurations of insulations and plasterboards. Failure times of load bearing LSF walls were also predicted based on the results from finite element thermal analyses. Finite element analysis results show that the use of cavity insulation was detrimental to the fire rating of LSF walls while the use of external insulation offered superior thermal protection to them. Effects of realistic design fire conditions are also presented in this paper.
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Jai, John, George S. Springer, Laszlo P. Kollar, and Helmut Krawinkler. "Reinforcing Masonry Walls with Composite Materials-Model." Journal of Composite Materials 34, no. 18 (September 2000): 1548–81. http://dx.doi.org/10.1106/38xx-ggb5-nxc9-tjha.
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In this investigation, a procedure is developed for determining the effectiveness of composite materials in retrofitting masonry buildings to reduce seismic damage. The reinforcement considered is a thin layer of fiber-reinforced composite applied to the wall in a wallpaper-like fashion. Models were developed which predict the behavior of masonry walls reinforced in such a fashion and subjected to static, in-plane normal and shear loads. Solid walls, as well as walls with openings (such as windows and doors), were considered. The models estimate the load-deflection characteristic of the wall, the load set at which the wall fails, and the deflection of the wall at the instant of failure. Numerical results were also generated which indicate that composite reinforcement applied in a wallpaper-like fashion may increase substantially the load carrying capacities of masonry walls.
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Sumner, D., and E. Brundrett. "Testing Three-Dimensional Bluff-Body Models in a Low-Speed Two-Dimensional Adaptive Wall Test Section." Journal of Fluids Engineering 117, no. 4 (December 1, 1995): 546–51. http://dx.doi.org/10.1115/1.2817299.
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Thin, sharp-edged disk models were evaluated in a low-speed two-dimensional adaptive flexible wall test section to determine the optimum adaptive wall testing environment for three-dimensional bluff-body models, by providing model testing recommendations for nominal solid blockage ratio and model span ratio. Drag coefficient measurements obtained under straight wall and adapted wall conditions showed that for a two-dimensional adaptive wall test section, the model span ratio imposes a more severe restriction upon model size than does the nominal solid blockage ratio. Minimum wall interference conditions were achieved with adapted walls for nominal solid blockage ratios less than 3 percent and model span ratios less than 21 percent, independent of the nominal test section aspect ratio, based on favorable comparison with previously-published experimental data. Data obtained under straight wall conditions confirmed that wall interference effects can only be neglected in conventional, straight-walled test sections for solid blockage ratios less than 0.5 percent and model span ratios less than 10 percent. The post-test boundary correction method of Maskell was successfully used to adjust the straight wall test section drag coefficient measurements of the larger models for wall interference effects, but no direct measurements of wall interference are used with this method. The results support the careful use of a two-dimensional wall adjustment strategy for three-dimensional nonlifting flows.
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Bhat, Akeel Firdos, and Er Vikas Kumar. "Comparative Study on Deflection of a Multistoried Building with Shear Wall and Core Wall." International Journal for Research in Applied Science and Engineering Technology 10, no. 5 (May 31, 2022): 3743–58. http://dx.doi.org/10.22214/ijraset.2022.43212.
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Abstract: To ensure the seismic effectiveness of highrise buildings different systems of lateral restraints are provided e.g., bracings, shear walls, core walls etc. In the present study, deflection of various joints, storeys & also the drifts have been gone through. For this purpose, 3 different models of multi-storeyed buildings were prepared consisting of a G+6 building with shear wall at the centre of edges on exterior walls, G+6 building with a core wall & G+8 building with a core wall were prepared using an integrated building designing software known as ETABS- 2016 (student version). A 3-bay building was modelled using M30 concrete mix and reinforcing steel bars of HYSD 415 for beams, columns, slabs as well as shear walls. After this pier labels were assigned to the shear walls. A variety of load cases like joint loads, dead loads, live loads, wind load in x-direction for terrain category 4, earthquake loads in x & y directions for zone II along with their combinations were assigned. The respective diaphragms were assigned to the three models & analysis was carried out at the end. The table of results was obtained and the deflection analysis was carried out to compare the relative effectiveness of shear walls & core walls at different locations of the multi-storeyed building. The codes taken into consideration during the progress of work were IS 456:2000 for plain and reinforced concrete, IS 875:2015 (Part 1) for wind loads & IS 1893:2002 for earthquake loads. Keywords: Earthquakes, Shear wall, Core wall, Lateral deflection.
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Gaillard, Emmanuel, Patrice Bergeron, and Valérie Deplano. "Influence of Wall Compliance on Hemodynamics in Models of Abdominal Aortic Aneurysm." Journal of Endovascular Therapy 14, no. 4 (August 2007): 593–99. http://dx.doi.org/10.1177/152660280701400423.
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Purpose: To determine complementary criteria to existing morphological criteria, which are not reliable but are used to justify surgical intervention to treat abdominal aortic aneurysm (AAA). Methods: An experimental study was conducted in which 2 models of AAA, 1 rigid and 1 soft, were used to study the influence of compliance on aneurysm dynamics. The heart rate was 70 beats per minute, and the mean flow rate was 1.02 L/min. Velocity measurements were made with particle image velocimetry in 2 planes parallel to flow (1 vertical and 1 horizontal). Results: The general flow patterns generated in the rigid AAA model were in agreement with the literature. In both models, a vortex occurred at the beginning of systolic deceleration in the proximal part of the AAA, near the anterior wall. The vortex remained confined to the proximal part during the entire cycle in the rigid model, whereas in the soft model, the vortex migrated to the distal segment during the cycle and impacted the AAA walls. This impact generated a local pressure increase on the wall. In the soft model, another vortex was created near the posterior wall. These vortices eroded and weakened the walls of the distal segment, which can cause rupture. Conclusion: Compliance of the aneurysm wall might become another criterion to justify surgical intervention.
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Eka Liani, Annisa, Indriati Martha Patuti, and Rifadli Bahsuan. "TINJAUAN KESTABILAN PERKUATAN LERENG MENGGUNAKAN DINDING KANTILEVER DAN DINDING GRAVITASI." Composite Journal 1, no. 1 (January 25, 2021): 26–32. http://dx.doi.org/10.37905/cj.v1i1.11.
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Parts of Gorontalo are hills and mountains close to community settlements, which are prone to landslides. To do a research on literature review that analyzes slope reinforcement models, which will be taken into consideration for slope improvement steps in Gorontalo. Slope reinforcement includes retaining walls, gravity walls, cantilever walls and crib walls. This research discusses slope reinforcement models and their stability behavior analysis. Secondary data is in the form of research journals on slope reinforcement models. Calculation data that will be used as experimental data for modeling other retrofitting walls are obtained from the results of research from one of the reviewed journals, namely multilevel gravity walls. The wall that will be analyzed is the retaining wall of a multilevel cantilever type of wall. Analysis of active soil pressure using the Rankine method and slope stability analysis using the slice method which is carried out with the help of 2D Slide software. Based on the results of the stability analysis of slope reinforcement with the selection of stratified cantilever wall reinforcement, the value of the safety factor against sliding (Fgs) is 1.63>1.5, the safety factor against overturning (Fgl) is 2.44>2.0, the safety factor against the collapse of carrying capacity (F) is 8.49>3.0, and the global safety factor value is 1.56>1.5. The value of the safety factor for shifting and rolling has decreased by 1% and 20% respectively compared to the gravitational wall. In the wall bearing capacity, there was an increase of 31%. Changes that occur in the safety factor in cantilevered walls are caused by changing factors in the dimensions of the walls which affect the strength of the structure in the soil holding force and the type of working principle of the walls. As for the global slope stability analyzed, there was a decrease in the safety factor by 5% after changing the type of reinforcement, but it showed that the slope was still stable, because the cantilevered wall type has a slender front wall dimension compared to the gravity wall which is more resistant to the risk of lateral slope movement.
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Simon, B. R., M. V. Kaufmann, M. A. McAfee, and A. L. Baldwin. "Finite Element Models for Arterial Wall Mechanics." Journal of Biomechanical Engineering 115, no. 4B (November 1, 1993): 489–96. http://dx.doi.org/10.1115/1.2895529.
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Arterial wall mechanics has been studied for nearly 200 years. This subject is of importance if we are to gain a fundamental understanding of this complex biological structure, as well as information needed to design prosthetics. Biomechanical arterial models continue to play an important role in the study of atherosclerosis, a disease of the arterial wall that is the chief cause of mortality and morbidity in the United States and the Western World. Over the past 20 years, the finite element model (FEM) has been used in a variety of ways to simulate the structural response of large arteries. Our purpose is to summarize the uses of FEMs in arterial mechanics. We will also indicate directions for future research in this area. A specialized FEM was described in the literature for the study of transport in the arterial wall, however the convection was not directly linked to arterial wall mechanics. In this paper special attention will be given to the development of FEMs based on the poroelastic view of arterial tissues which couple wall deformation, free tissue fluid motion, and associated transport phenomena in the arterial wall. In the future such models should provide fundamental quantitative information relating arterial wall mechanics and transport which may lead to a better understanding of both normal arterial physiology and atherogenesis.
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Chen, Hui, Panagiotis Asteris, Danial Jahed Armaghani, Behrouz Gordan, and Binh Pham. "Assessing Dynamic Conditions of the Retaining Wall: Developing Two Hybrid Intelligent Models." Applied Sciences 9, no. 6 (March 13, 2019): 1042. http://dx.doi.org/10.3390/app9061042.
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The precise estimation and forecast of the safety factor (SF) in civil engineering applications is considered as an important issue to reduce engineering risk. The present research investigates new artificial intelligence (AI) techniques for the prediction of SF values of retaining walls, as important and resistant structures for ground forces. These structures have complicated performances in dynamic conditions. Consequently, more than 8000 designs of these structures were dynamically evaluated. Two AI models, namely the imperialist competitive algorithm (ICA)-artificial neural network (ANN), and the genetic algorithm (GA)-ANN were used for the forecasting of SF values. In order to design intelligent models, parameters i.e., the wall thickness, stone density, wall height, soil density, and internal soil friction angle were examined under different dynamic conditions and assigned as inputs to predict SF of retaining walls. Various models of these systems were constructed and compared with each other to obtain the best one. Results of models indicated that although both hybrid models are able to predict SF values with a high accuracy and they can be introduced as new models in the field, the retaining wall performance could be properly predicted in dynamic conditions using the ICA-ANN model. Under these conditions, a combination of engineering design and artificial intelligence techniques can be used to control and secure retaining walls in dynamic conditions.
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Saeed, Ahmed, Hadee Mohammed Najm, Amer Hassan, Shaker Qaidi, Mohanad Muayad Sabri Sabri, and Nuha S. Mashaan. "A Comprehensive Study on the Effect of Regular and Staggered Openings on the Seismic Performance of Shear Walls." Buildings 12, no. 9 (August 23, 2022): 1293. http://dx.doi.org/10.3390/buildings12091293.
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Shear walls have high strength and stiffness, which could be used at the same time to resist large horizontal loads and weight loads, making them pretty beneficial in several structural engineering applications. The shear walls could be included with openings, such as doors and windows, for relevant functional requirements. In the current study, a building of G + 13 stories with RC shear walls with and without openings has been investigated using ETABS Software. The seismic analysis is carried out for the determination of parameters like shear forces, drift, base shear, and story displacement for numerous models. The regular and staggered openings of the shear wall have been considered variables in the models. The dynamic analysis is carried out with the help of ETABS software. It has been observed that shear walls without openings models perform better than other models, and this is in agreement with the previous studies published in this area. This investigation also shows that the seismic behaviour of the shear wall with regular openings provides a close result to the shear wall with staggered openings. At the roof, the displacement of the model with regular openings was 38.99 mm and approximately 39.163 mm for the model with staggered openings. However, the model without a shear wall experienced a displacement of about 56 mm at the roof. Generally, it can be concluded that the openings have a substantial effect on the seismic behaviour of the shear wall, and that should be taken into consideration during the construction design. However, the type of opening (regular or staggered) has a slight effect on the behaviour of shear walls.
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Kalitzin, Georgi, Gorazd Medic, Gianluca Iaccarino, and Paul Durbin. "Near-wall behavior of RANS turbulence models and implications for wall functions." Journal of Computational Physics 204, no. 1 (March 2005): 265–91. http://dx.doi.org/10.1016/j.jcp.2004.10.018.
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Cai, Shang-Gui, and Pierre Sagaut. "Explicit wall models for large eddy simulation." Physics of Fluids 33, no. 4 (April 2021): 041703. http://dx.doi.org/10.1063/5.0048563.
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Adrian, R. J. "Closing In on Models of Wall Turbulence." Science 329, no. 5988 (July 8, 2010): 155–56. http://dx.doi.org/10.1126/science.1192013.
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Sanghi, Sanjeev, and Nadine Aubry. "Mode interaction models for near-wall turbulence." Journal of Fluid Mechanics 247 (February 1993): 455–88. http://dx.doi.org/10.1017/s0022112093000527.
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Intermittent bursting events, similar to those characterizing the dynamics of near-wall turbulence, have been observed in a low-dimensional dynamical model (Aubry et al. 1988) built from eigenfunctions of the proper orthogonal decomposition (Lumley 1967). In the present work, we investigate the persistency of the intermittent behaviour in higher - but still of relatively low-dimensional dynamical systems. In particular, streamwise variations which were not accounted for in an explicit way in Aubry et al.'s model are now considered. Intermittent behaviour persists but can be of a different nature. Specifically, the non-zero streamwise modes become excited during the eruptive events so that rolls burst downstream into smaller scales. When structures have a finite length, they travel at a convection speed approximately equal to the mean velocity at the top of the layer (y+ ≈ 40). In all cases, intermittency seems to be due to homoclinic cycles connecting hyperbolic fixed points or more complex (apparently chaotic) limit sets. While these sets lie in the zero streamwise modes invariant subspace, the connecting orbits consist of nonzero streamwise modes travelling downstream. Chaotic limit sets connected by quasi-travelling waves have also been observed in a spatio-temporal chaotic regime of the Kuramoto–Sivashinsky equation (Aubry & Lian 1992a). When the limit sets lose their steadiness, the elongated rolls become randomly active, as they probably are in the real flow. A coherent structure study in our resulting flow fields is performed in order to relate our findings to experimental observations. It is shown that streaks, streamwise rolls, horseshoe vortical structures and shear layers, present in our models, are all connected to each other. Finally, criteria to determine a realistic value of the eddy viscosity parameter are developed.
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Ooguri, Hirosi, Piotr Sułkowski, and Masahito Yamazaki. "Wall Crossing as Seen by Matrix Models." Communications in Mathematical Physics 307, no. 2 (September 4, 2011): 429–62. http://dx.doi.org/10.1007/s00220-011-1330-x.
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Piomelli, Ugo. "Wall-layer models for large-eddy simulations." Progress in Aerospace Sciences 44, no. 6 (August 2008): 437–46. http://dx.doi.org/10.1016/j.paerosci.2008.06.001.
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Ng, E. Y. K., H. Y. Tan, H. N. Lim, and D. Choi. "Near-wall function for turbulence closure models." Computational Mechanics 29, no. 2 (August 1, 2002): 178–81. http://dx.doi.org/10.1007/s00466-002-0331-1.
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Rusthi, Mohamed, Poologanathan Keerthan, Mahen Mahendran, and Anthony Ariyanayagam. "Investigating the fire performance of LSF wall systems using finite element analyses." Journal of Structural Fire Engineering 8, no. 4 (December 11, 2017): 354–76. http://dx.doi.org/10.1108/jsfe-04-2016-0002.
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Purpose This research was aimed at investigating the fire performance of LSF wall systems by using 3-D heat transfer FE models of existing LSF wall system configurations. Design/methodology/approach This research was focused on investigating the fire performance of LSF wall systems by using 3-D heat transfer finite element models of existing LSF wall system configurations. The analysis results were validated by using the available fire test results of five different LSF wall configurations. Findings The validated finite element models were used to conduct a parametric study on a range of non-load bearing and load bearing LSF wall configurations to predict their fire resistance levels (FRLs) for varying load ratios. Originality/value Fire performance of LSF wall systems with different configurations can be understood by performing full-scale fire tests. However, these full-scale fire tests are time consuming, labour intensive and expensive. On the other hand, finite element analysis (FEA) provides a simple method of investigating the fire performance of LSF wall systems to understand their thermal-mechanical behaviour. Recent numerical research studies have focused on investigating the fire performances of LSF wall systems by using finite element (FE) models. Most of these FE models were developed based on 2-D FE platform capable of performing either heat transfer or structural analysis separately. Therefore, this paper presents the details of a 3-D FEA methodology to develop the capabilities to perform fully-coupled thermal-mechanical analyses of LSF walls exposed to fire in future.
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Badarloo, Baitollah, and Faezeh Jafari. "A Numerical Study on the Effect of Position and Number of Openings on the Performance of Composite Steel Shear Walls." Buildings 8, no. 9 (September 1, 2018): 121. http://dx.doi.org/10.3390/buildings8090121.
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Use of composite steel shear walls (CSSW) in earthquake-resistant structures has grown in recent years. However, no thorough information exists on their performance, especially in cases where openings are present. In the present study, in order to first validate the analysis method, ABAQUS was used to model the studied composite shear wall with gap at UC-Berkeley, according to the results of which, a good agreement between the experimental and analytical models was observed. Then, the effect of the position and number of the openings on the performance of the walls was addressed. To this end, models with various openings, including openings close to the beam/column, horizontal/vertical openings and distributing opening, were prepared and analyzed. The results indicate that the maximum reduction in stiffness and strength occurred in walls with single openings. The size of opening and the opening’s area significantly affect shear wall performance. Ultimately, artificial neural network and fitness function tools were employed to obtain predictive models for shear wall performance. A neural network has proven an appropriate alternative method for predicting the displacement, stress, and strength of the composite shear wall.
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Dadayan, Tigran, and Ehsan Roudi. "Investigations of RC Shear Wall-Frame Structures with Various Openings in Walls under Earthquake Loading." Advanced Materials Research 1020 (October 2014): 242–47. http://dx.doi.org/10.4028/www.scientific.net/amr.1020.242.
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Almost all high-rise buildings have been constructed in the Republic of Armenia for past twenty-five years are Reinforced Concrete (RC) shear wall–frame structures, where shear walls provide most of the stiffness of buildings. The walls in these buildings are designed to sustain earthquake and wind loads. Vulnerability of them during earthquake action depends on many different factors. Some of them are the openings and its location in the walls. Usage of ground stories as parking and garages is demanded large openings in shear walls therefore determination of ultimate sizes of openings is important problems for designers. In this paper, FEM (Finite Element Method) models are used for investigation of stress-strain state of RC wall–frame buildings with various openings in the walls under action of seismic forces. Limitation of size and position of openings are considered in the paper taking into account of building code of Armenia. Various schemes of openings are considered in the article. The existing experimental data of shear walls were performed in various laboratories have been compared with our numerical investigation of RC models based on nonlinear computer analyses. Dynamic analyses of structures using accelerograms are showed sequence of damages in RC wall-frame models. The recommendations for limitation of ratio area of an opening to the whole area of a wall are proposed at the end of the article.
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Kazaz, İlker, Polat Gülkan, and Ahmet Yakut. "Deformation Limits for Structural Walls with Confined Boundaries." Earthquake Spectra 28, no. 3 (August 2012): 1019–46. http://dx.doi.org/10.1193/1.4000059.
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For accurate analytical assessment of performance and damage in reinforced concrete members, well-defined deformation limits at particular damage states are required. With advanced and computationally intensive finite element analyses, we establish deformation limits at yield and ultimate limit states for adequately confined rectangular reinforced concrete structural walls in terms of drift ratio, plastic rotation, and curvature. To investigate the deformation limits of structural walls, a parametric study on isolated cantilever wall models is performed. The primary variables of the parametric study are the shear-span-to-wall-length ratio, wall length, axial load ratio, normalized shear stress, the amount of horizontal web reinforcement, and the amount of longitudinal reinforcement at the confined boundary of structural wall models. Expressions and limit values are proposed for yield and ultimate deformation capacity of structural walls, based on the most influential parameters. The proposed equations are found to be promising when compared to results of experiments.
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Wang, Shunli, Daying Dai, Praveen Kolumam Parameswaran, Ramanathan Kadirvel, Yong-Hong Ding, Anne M. Robertson, and David F. Kallmes. "Rabbit aneurysm models mimic histologic wall types identified in human intracranial aneurysms." Journal of NeuroInterventional Surgery 10, no. 4 (August 2, 2017): 411–15. http://dx.doi.org/10.1136/neurintsurg-2017-013264.
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BackgroundSemiquantitative scales correlate histopathologic findings in the walls of human aneurysms with rupture status.ObjectiveTo apply a semiquantitative scale to the rabbit elastase-induced aneurysm model to determine whether rabbit histologic types mimic the full range of histologic subtypes of humans.Materials and methodsTwenty-seven elastase-induced female rabbit aneurysms were studied, harvested at 2 weeks (n=5) and 12 weeks (n=22). Paraffin-embedded sections received hematoxylin-eosin and Verhoeff-Van Gieson staining. Immunohistochemistry was performed for α-smooth muscle actin and CD31 for endothelial cells. A semiquantitative scale was used for scoring based on human aneurysm tissue, divided into four subtypes according to cellular and extracellular matrix findings: type A, linear organized smooth muscle cells (SMCs) and intact endothelium; type B, thickened wall with disorganized, proliferating SMCs; type C, thick, collagenized and hypocellular wall with or without organizing thrombosis, and type D, extremely thin, hypocellular wall. Separate scoring was performed of the aneurysm neck and proximal and distal zones.ResultsFindings compatible with all subtypes of human aneurysm tissue were identified. Types A and C were found in 13 (48%) and 11 (41%) of 27 aneurysms and in the proximal and distal wall at both time points. Type B was found in 16 aneurysms (59%), exclusively at the neck at both time points; type D, in 14 aneurysms (52%), exclusively at proximal and distal zones of 12-week aneurysms.ConclusionsThe wall of elastase-induced rabbit aneurysm demonstrates histologic findings similar to the four categories of human cerebral aneurysms based on cellular and extracellular wall content.
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Movahednia, Mehrdad, S. Mohammad Mirhosseini, and Ehsanollah Zeighami. "Numerical Evaluation of the Behavior of Steel Frames with Gypsum Board Infill Walls." Advances in Civil Engineering 2019 (March 3, 2019): 1–12. http://dx.doi.org/10.1155/2019/6846139.
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In this paper, the behavior of steel frames with gypsum board infill walls is studied through finite element simulation. For this purpose, a typical steel frame with infill wall which had been previously tested is considered as a benchmark model. The accuracy of a numerical model is verified by calibrating the results of the finite element simulation against those of a corresponding experimental specimen. In the next step, a parametric study is performed on four models in order to study the effects of gypsum board thickness, inclusion of fibers as reinforcement in the infill wall, and local strengthening of the peripheral regions of the infill wall. Each of these factors is related to considerable performance improvement such as strength and ductility of the models. It is observed that adding fibers to the infill wall leads to increase in the strength and ductility of the models up to 3.2 and 6.3 times, respectively. Doubling the thickness of the infill wall results in an increase of 6.7 and 3.3 times in strength and stiffness, respectively; however, this modification causes a significant decrease in the ductility of the infilled frames. Negligible improvement in strength and ductility is achieved through local strengthening of the peripheral regions of the infill walls, whereas it leads to a 30% increase in the stiffness of the models.
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Salameh, Tareq, and Bengt Sunden. "A numerical investigation of heat transfer in a smooth bend part of a U-duct." International Journal of Numerical Methods for Heat & Fluid Flow 24, no. 1 (December 20, 2013): 137–47. http://dx.doi.org/10.1108/hff-03-2012-0066.
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Purpose – The aim of this paper is to study two-dimensional numerical simulations of the flow and temperature fields inside the bend (turn) part of a U-duct. Design/methodology/approach – Several turbulence models based on two and five equations were used to solve the momentum and energy equations inside the bend (turn) part of the U-duct. For two-equation models, both the renormalization group and realizable k-ɛ turbulence models were implemented. The five-equation model used is a Reynolds stress model with different wall boundary conditions. Standard, non-equilibrium and enhanced wall functions were used in parallel with the two- and five-equation models to treat the turbulent flow near the duct walls. Findings – Several turbulence models were used to simulate the flow and temperature fields along the bend part of a U-duct with different inlet and thermal boundary conditions. The numerical results indicate that the renormalization and realizable k-ɛ turbulence models with standard wall function treatment gave the best results when compared with experimental data obtained for similar conditions. Research limitations/implications – For heat transfer analysis, two different thermal boundary conditions, i.e. constant wall temperature and constant heat flux at the wall are implemented. The results are calculated for Reynolds number equal 20,000. Practical implications – The results can be used in designing heat exchangers, piping and duct systems, and internal passage cooling of gas turbine blades. Originality/value – The numerical results obtained here concentrate on the detailed investigation of flow and temperature field at the outer wall of the bend part. Different boundary conditions at the inlet and the outer bend walls of the U-duct were applied to study how these boundary conditions affect the flow and temperature fields.
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Firoozi, Ali Akbar, Mohd Raihan Taha, S. M. Mir Moammad Hosseini, and Ali Asghar Firoozi. "Examination of the Behavior of Gravity Quay Wall against Liquefaction under the Effect of Wall Width and Soil Improvement." Scientific World Journal 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/325759.
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Deformation of quay walls is one of the main sources of damage to port facility while liquefaction of backfill and base soil of the wall are the main reasons for failures of quay walls. During earthquakes, the most susceptible materials for liquefaction in seashore regions are loose saturated sand. In this study, effects of enhancing the wall width and the soil improvement on the behavior of gravity quay walls are examined in order to obtain the optimum improved region. The FLAC 2D software was used for analyzing and modeling progressed models of soil and loading under difference conditions. Also, the behavior of liquefiable soil is simulated by the use of “Finn” constitutive model in the analysis models. The “Finn” constitutive model is especially created to determine liquefaction phenomena and excess pore pressure generation.
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Wirth, Ulrich, Nuri Shirali, Vladimír Křístek, and Helmut Kurth. "HYBRID SHEARWALL SYSTEM — SHEAR STRENGTH AT THE INTERFACE CONNECTION." Acta Polytechnica 53, no. 6 (December 31, 2013): 913–22. http://dx.doi.org/10.14311/ap.2013.53.0913.
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Based on a series of alternating, displacement-controlled load tests on ten one-third scale models, to study the behaviour of the interface of a hybrid shear wall system, it was proved that the concept of hybrid construction in earthquake prone regions is feasible. The hybrid shear-wall system consists of typical reinforced concrete shear walls with composite edge members or flanges. Ten different anchorage bar arrangements were developed and tested to evaluate the column-shearwall interface behaviour under cyclic shear forces acting along the interface between column and wall panel. Finite element models of the test specimens were developed that were capable of capturing the integrated concrete and reinforcing steel behaviour in the wall panels. Special models were developed to capture the interface behaviour between the edge columns and the shear wall. A comparison between the experimental results and the numerical results shows excellent agreement, and clearly supports the validity of the model developed for predicting the non-linear response of the hybrid wall system under various load conditions.
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Bandyopadhyay, Tirtha Sathi, Sumit Kumar Nandan, and Pradipta Chakrabortty. "Evaluation of Wall Inclination Effect on the Dynamic Response of Mechanically Stabilized Earth Walls Using Shaking Table Tests." International Journal of Geotechnical Earthquake Engineering 13, no. 1 (January 1, 2022): 1–21. http://dx.doi.org/10.4018/ijgee.310052.
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Shaking table tests were conducted in this study to determine the effect of facing wall inclinations, and the density of the backfill. Reduced-scale models reinforced with two layers of geogrid and fine sand as backfill were studied to identify the dynamic behaviour of mechanically stabilised earth walls. Five different angles of inclination of the facing walls were considered to study its effect on the responses. All seven models were excited by stepped amplitude sinusoidal base accelerations with incrementally increasing peak ground acceleration amplitudes and constant frequencies. The model wall's responses are compared in terms of the acceleration amplification and lateral displacements of the wall measured at different elevations. These tests revealed that horizontal displacement of the wall was maximum at the middle position of the wall. Minimum displacement was observed in the 20° inclined wall towards the backfill soil, which was 35% lower than the vertical wall. The accelerations were amplified along with the wall height. The wall having 10° inward inclination with dense backfill showed the maximum amplification (for high PGA). In the last part, an analytical study was conducted to calculate the acceleration amplifications and compared them with the experimental results. Higher values were observed in the case of the analytical approach as compared to the experimental study.
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Carvalho, Violeta, Filipa Carneiro, Ana C. Ferreira, Vasco Gama, José C. Teixeira, and Senhorinha Teixeira. "Numerical Study of the Unsteady Flow in Simplified and Realistic Iliac Bifurcation Models." Fluids 6, no. 8 (August 14, 2021): 284. http://dx.doi.org/10.3390/fluids6080284.
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Cardiovascular diseases are a major cause of death and disability worldwide and they are commonly associated with the occurrence of atherosclerotic plaque deposition in the vessel walls, a process denoted as atherosclerosis. This is a chronic and progressive inflammatory disease of large-/medium-sized blood vessels that affects blood flow profiles, with the abdominal aorta and its branches being one of the locations prone to the development of this pathology, due to their curvatures and bifurcations. In this regard, the effect of flow patterns was studied and compared for both a simplified three-dimensional model of aorta bifurcation on the iliac arteries and a realistic model of iliac bifurcation, which was constructed from a computational tomography medical image. The flow patterns were analyzed in terms of velocity and wall shear stress distribution, but a special focus was given to the size and location of the recirculation zone. The simulations were performed using the Computational Fluid Dynamics software, FLUENT, taking into account the cardiac cycle profile at the infrarenal aorta. The shear stress and the velocity distribution observed for both models indicated that higher shear stress occurred along the flow divider wall (inner wall) and low shear stress occurred along the outer walls. In addition, the results demonstrated that the wall shear stress profiles were deeply affected by the transient profile of the cardiac cycle, with the deceleration phase being the most critical phase to the occurrence of backflow.
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Mesri, Yaser, Hamid Niazmand, Amin Deyranlou, and Mahmood Reza Sadeghi. "Fluid-structure interaction in abdominal aortic aneurysms: Structural and geometrical considerations." International Journal of Modern Physics C 26, no. 04 (February 25, 2015): 1550038. http://dx.doi.org/10.1142/s0129183115500382.
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Rupture of the abdominal aortic aneurysm (AAA) is the result of the relatively complex interaction of blood hemodynamics and material behavior of arterial walls. In the present study, the cumulative effects of physiological parameters such as the directional growth, arterial wall properties (isotropy and anisotropy), iliac bifurcation and arterial wall thickness on prediction of wall stress in fully coupled fluid-structure interaction (FSI) analysis of five idealized AAA models have been investigated. In particular, the numerical model considers the heterogeneity of arterial wall and the iliac bifurcation, which allows the study of the geometric asymmetry due to the growth of the aneurysm into different directions. Results demonstrate that the blood pulsatile nature is responsible for emerging a time-dependent recirculation zone inside the aneurysm, which directly affects the stress distribution in aneurismal wall. Therefore, aneurysm deviation from the arterial axis, especially, in the lateral direction increases the wall stress in a relatively nonlinear fashion. Among the models analyzed in this investigation, the anisotropic material model that considers the wall thickness variations, greatly affects the wall stress values, while the stress distributions are less affected as compared to the uniform wall thickness models. In this regard, it is confirmed that wall stress predictions are more influenced by the appropriate structural model than the geometrical considerations such as the level of asymmetry and its curvature, growth direction and its extent.
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SANCIOĞLU, Sadrettin, Hasan Furkan SOYDOĞAN, and Hüsnü CAN. "The Effect of Different Infill Wall Materials and Their Location in Plan on the Behaviour of a Reinforced Concrete Building." Uluslararası Muhendislik Arastirma ve Gelistirme Dergisi 14, no. 2 (July 31, 2022): 457–74. http://dx.doi.org/10.29137/umagd.1028494.
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It is known that infill walls affect the strength and rigidity of the structure, although the effect of infill walls is neglected in the calculation and design of reinforced concrete structures. In this study, the effects of two different infill wall materials, namely vertically perforated brick and gas concrete block, and different wall locations on a ten-storey symmetrical structure with six spans in the x-direction and three spans in the y-direction with a reinforced concrete framed load-carrying system were investigated. According to Turkey Building Earthquake Code-2018, 16 models were examined in the SAP2000 program, which is based on the finite element method. Infill walls with different materials are defined in the program as a single equivalent pressure bar according to their properties. The effects of different infill wall types and different infill wall placements on the horizontal displacement of a reinforced concrete framed structure, relative storey drifts, strength, and the performance target of the building under horizontal and vertical loads were examined on the models made. As a result of the research, it was observed that infill wall material types and infill wall location significantly reduced the horizontal displacement of the structure in both directions, while increasing the rigidity of the structure and decreasing its period.
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Zamiar, Zenon, Andrzej Surowiecki, and Piotr Saska. "Model Studies of Distortion Condition Resistance Wall from Gabionic Elements." Logistics and Transport 43, no. 3 (2019): 47–56. http://dx.doi.org/10.26411/83-1734-2015-3-43-9-19.
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Retaining walls have been classified and characterized as structures protecting road or railway embankments against landslides. Particular attention was focused on retaining structures classified as light [1-3, 5-12, 14-24], which include, among others, walls made of gabions. Physical models of the gabion retaining wall, prepared on a laboratory scale, test stand and how to perform spatial deformation tests are presented. The models differed in the number and dimensions of gabions. On the basis of measured horizontal deformations of embankment models with a gabion wall, which were subjected to vertical static pressure at the level of the embankment ceiling, the values of basic strength parameters were determined. In particular, the value calculated: horizontal pressure coefficient, shear strength and modulus of deformation. The variability of the values of these parameters was estimated as a function of variable factors related to the gabion wall configuration (determined by the number and dimensions of gabions) and the value of the external load test.
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Zamiar, Zenon, Andrzej Surowiecki, and Piotr Saska. "Model studies of distortion condition resistance wall from gabionic elements." Logistics and Transport, no. 43 (2019): 47. http://dx.doi.org/10.26411/83-1734-2015-4-43-9-19.
Full textAbstract:
Retaining walls have been classified and characterized as structures protecting road or railway embankments against landslides. Particular attention was focused on retaining structures classified as light [1-3, 5-12, 14-24], which include, among others, walls made of gabions. Physical models of the gabion retaining wall, prepared on a laboratory scale, test stand and how to perform spatial deformation tests are presented. The models differed in the number and dimensions of gabions. On the basis of measured horizontal deformations of embankment models with a gabion wall, which were subjected to vertical static pressure at the level of the embankment ceiling, the values of basic strength parameters were determined. In particular, the value calculated: horizontal pressure coefficient, shear strength and modulus of deformation. The variability of the values of these parameters was estimated as a function of variable factors related to the gabion wall configuration (determined by the number and dimensions of gabions) and the value of the external load test.
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Sun, Xiang, Peiyu Liu, Zhelong Jiang, Yuqing Yang, Zhe Wang, and Zaigen Mu. "Analysis of Design Method and Mechanical Properties of Plug-In Composite Shear Wall." Metals 13, no. 1 (January 16, 2023): 177. http://dx.doi.org/10.3390/met13010177.
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Assembly buildings are an important direction for the future development of the construction field. They can be prefabricated in the factories and then assembled on-site, which significantly improves construction efficiency. The shear walls are the most important lateral force-resisting elements in building structures, and at this stage, there are more and more studies on the prefabricated shear wall. In this paper, a new composite shear wall structure is proposed. The composite shear wall is a part of a prefabricated building, which is prefabricated into a single shear wall unit in the factory. During the construction, the upper and lower prefabricated shear wall units are connected by the plug-in. The design methods of splicing connection are given for the design of this composite shear wall structure. Eleven composite wall models under different parameters are established by using the finite element method, especially the fine modeling of the upper and lower connection parts. Compared with the conventional composite shear wall model of the same dimensions, the mechanical behaviors of the two models are similar. In the simulation of cyclic loading, the new composite shear wall shows good ductility and energy dissipation capacity, and also meets the established requirements of building seismic performance. Therefore, it can be concluded that the new prefabricated composite shear walls have good development prospects and application values.
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Jasiński, Radosław, and Iwona Galman. "Testing Joints between Walls Made of AAC Masonry Units." Buildings 10, no. 4 (April 2, 2020): 69. http://dx.doi.org/10.3390/buildings10040069.
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Joints between walls are very important for structural analysis of each masonry building at the global and local level. This issue has often been neglected in the case of traditional joints and relatively squat walls. At present, the issue of wall joints is becoming particularly important due to the continuous drive for simplifying structures, introducing new technologies and materials. Eurocode 6 and other standards (American, Canadian, Chinese, and Japanese) recommend inspecting joints between walls, but no detailed procedures have been specified. This paper presents our own tests on joints between walls made of autoclaved aerated concrete (AAC) masonry units. Tests included reference models composed of two wall panels joined perpendicularly with a standard masonry bond (six models), with classic steel and modified connectors (twelve models). The shape and size of test models and the structure of a test stand were determined on the basis of the analysis of the current knowledge, pilot studies and numerical FEM (Finite Element Method) - based analyses. The analyses referred to the morphology and failure mechanism of models. Load-displacement relationships for different types of joints were compared and obtained results were related to results for reference models. The mechanisms of cracking and failure was found to vary, and clear differences in the behaviour and load capacity of each type of joint were observed. The individual working phases of joints were determined and defined, and an empirical approach was proposed for the determination of forces and displacement of wall joints.
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Ganbaatar, Ariunaa, Takuro Mori, Shinya Matsumoto, and Ryo Inoue. "Reinforced Effect on Brick Wall Using Timber Wall as a Retrofitting Method." Buildings 12, no. 7 (July 9, 2022): 978. http://dx.doi.org/10.3390/buildings12070978.
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The purpose of this study is to utilize timber material to enhance the in-plane shear strength and deformation capacity of a brick wall. The proposed strengthening method is light-weight and easy to assemble and includes a timber frame, plywood panel, M12 threaded rod with chemical epoxy, and the hold-down anchor. To evaluate the effectiveness of the reinforced brick wall, three walls were tested under a cyclic horizontal load and static compression stress: the brick wall (BW wall), the reinforced brick wall with timber (BW-T wall), and the reinforced brick wall with timber and the hold-down anchor (BW-TA wall). The proposed prediction method of the Kamiya and Inayama Murakami models assessed the BW-TA wall. The rocking was caused by the failure of BW and BW-T walls. However, because the BW-T wall failed in the lowest part of the wall, the timber part retained the original shape of the brick wall. When the diagonal on the BW-TA wall failed, the horizontal load at maximum load increased by 22%, and the drift angle calculated from the diagonal measurement increased 4.6 times.
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Shin, Seung-Ho, Jae-Sung Kwon, June-Sung Shim, and Jong-Eun Kim. "Evaluating the Three-Dimensional Printing Accuracy of Partial-Arch Models According to Outer Wall Thickness: An In Vitro Study." Materials 14, no. 22 (November 9, 2021): 6734. http://dx.doi.org/10.3390/ma14226734.
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The printing accuracy of three-dimensional (3D) dental models using photopolymer resin affects dental diagnostic procedures and prostheses. The accuracy of research into the outer wall thickness and printing direction data for partial-arch model printing has been insufficient. This study analyzed the effects of wall thickness and printing direction accuracy. Anterior and posterior partial-arch models were designed with different outer wall thicknesses. After 3D printing, a trueness analysis was performed. Those with full-arch models were the control group. The full-arch model had an error value of 73.60 ± 2.61 µm (mean ± standard deviation). The error values for the partial-arch models with 1-, 2-, and 3-mm thick outer walls were 54.80 ± 5.34, 47.58 ± 7.59, and 42.25 ± 9.19 μm, respectively, and that for the fully filled model was 38.20 ± 4.63 μm. The printing accuracies differed significantly between 0 degrees and 60 degrees, at 49.54 ± 8.16 and 40.66 ± 6.80 μm, respectively (F = 153.121, p < 0.001). In conclusion, the trueness of the partial-arch model was better than that of the full-arch model, and models with thick outer walls at 60 degrees were highly accurate.
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Taghizadeh, Hadi, and Mohammad Tafazzoli Shadpour. "Structurally Motivated Models of the Arterial Wall Tissue." Journal of Multiscale Modelling 05, no. 04 (December 2013): 1330002. http://dx.doi.org/10.1142/s1756973713300025.
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Mechanical characteristics of soft biological tissues mostly depend on their hierarchy at different scales from nano- to macro-structure. It is shown that arterial wall tissue is highly sensitive to its mechanical environment and any alteration in mechanical factors such as blood pressure, triggers physio- pathological processes within arterial wall. Quantification of these mechanical properties will provide us with deeper insights of ongoing biological events. In this context, mechanical contributions of wall constituents in health and diseases are of growing interest. Hence, this review is concerned with mechanical models of arterial wall tissue with a focus on microstructurally motivated representations.