Deformation Of Frame Research Articles

Collapsible roof attachment – An all-weather protective shield for two-wheeler drivers

The effect of rain on two-wheeler users in India can be seen everywhere. An attempt is made to design and develop a roof attachment for Indian two-wheelers. The transparent Polyvinyl chloride roof designed here covers the side as well as front and has less drag force and lift compared to other existing attachments. The roof, front support and rear support structures are detachable using fasteners, which makes the assembly modular and easier for stoving. The front and rear supports are made of steel and their height can be adjusted with a ball catch mechanism. The rear support can be used as handrail. Computational Fluid Dynamics (CFD) software and static structural analysis software are used to evaluate the drag force, lift force and also the deformation and stresses of the support frames. Based on conceptual designs an optimal design has been arrived at for manufacturing the attachment. The parts required for assembly have been purchased and fabricated. The final attachment is assembled on an Indian scooter and tested in the real time environment.

Experimental investigation of strengthening of masonry-infilled RC frames using prefabricated engineered cementitious composite panels

Cement-based composite materials such as engineered cementitious composites (ECCs) are appropriate for retrofitting buildings because of their high tensile strength and strain. This research evaluated the lateral behavior of strengthened masonry-infilled reinforced concrete (RC) frames reinforced with prefabricated engineered cementitious composite (PECC) panels. The goals of the proposed technique were to increase the energy absorption capacity and the lateral capacity of infilled RC frames and protect the stability of the masonry infills after cracking and brittle failure in the out-of-plane direction, which can contribute to the seismic vulnerability of a structure. The mechanical characteristics of the ECC materials, such as the tensile strength and strain and multiple cracks, were first determined. Then, nine diagonal compression tests were done on masonry panels strengthened with PECC panels. In these tests, two types of connection were compared and the best one was selected. Next, an existing one-story RC moment frame with one bay was scaled down for testing under lateral cyclic loading. The results indicated that the strength, deformation, stiffness, and energy absorption of the RC frames increased considerably. Additionally, the effects of the precast panel thickness, performance of the connections, and type of damage sustained were compared between the different types of tests. Overall, the PECC panels connected to the infill wall with the proposed connections improved the lateral behavior of the system in the in-plane direction and markedly mitigated the risk of collapse by confining the masonry infill wall.

Experimental testing of decoupled masonry infills with steel anchors for out-of-plane support under combined in-plane and out-of-plane seismic loading

Because of simple construction process, high energy efficiency, significant fire resistance and excellent sound isolation, masonry infilled reinforced concrete (RC) frame structures are very popular in most of the countries in the world, as well as in seismic active areas. However, many RC frame structures with masonry infills were seriously damaged during earthquake events, as the traditional infills are generally constructed with direct contact to the RC frame which brings undesirable infill/frame interaction. This interaction leads to the activation of the equivalent diagonal strut in the infill panel, due to the RC frame deformation, and combined with seismically induced loads perpendicular to the infill panel often causes total collapses of the masonry infills and heavy damages to the RC frames. This fact was the motivation for developing different approaches for improving the behaviour of masonry infills, where infill isolation (decoupling) from the frame has been more intensively studied in the last decade. In-plane isolation of the infill wall reduces infill activation, but causes the need for additional measures to restrain out-of-plane movements. This can be provided by installing steel anchors, as proposed by some researchers. Within the framework of European research project INSYSME (Innovative Systems for Earthquake Resistant Masonry Enclosures in Reinforced Concrete Buildings) the system based on a use of elastomers for in-plane decoupling and steel anchors for out-of-plane restrain was tested. This constructive solution was tested and deeply investigated during the experimental campaign where traditional and decoupled masonry infilled RC frames with anchors were subjected to separate and combined in-plane ‬and out-of-plane loading. Based on a detailed evaluation and comparison of the test results, the performance and effectiveness of the developed system are illustrated.

Nonassociative black ellipsoids distorted by R-fluxes and four dimensional thin locally anisotropic accretion disks

We construct nonassociative quasi-stationary solutions describing deformations of Schwarzschild black holes, BHs, to ellipsoid configurations, which can be black ellipsoids, BEs, and/or BHs with ellipsoidal accretion disks. Such solutions are defined by generic off-diagonal symmetric metrics and nonsymmetric components of metrics (which are zero on base four dimensional, 4-d, Lorentz manifold spacetimes but nontrivial in respective 8-d total (co) tangent bundles). Distorted nonassociative BH and BE solutions are found for effective real sources with terms proportional to hbar kappa (for respective Planck and string constants). These sources and related effective nontrivial cosmological constants are determined by nonlinear symmetries and deformations of the Ricci tensor by nonholonomic star products encoding R-flux contributions from string theory. To generate various classes of (non) associative /commutative distorted solutions we generalize and apply the anholonomic frame and connection deformation method for constructing exact and parametric solutions in modified gravity and/or general relativity theories. We study properties of locally anisotropic relativistic, optically thick, could and thin accretion disks around nonassociative distorted BHs, or BEs, when the effects due to the rotation are negligible. Such configurations describe angular anisotropic deformations of axially symmetric astrophysical models when the nonassociative distortions are related to the outer parts of the accretion disks.

Hysteretic behavior of circular tubed reinforced concrete column to steel beam frames

Tubed reinforced concrete (TRC) columns have good deformability and energy dissipation capacity under horizontal cyclic loads; and even with plastic hinges formed at the column ends, the corresponding frame structure may still have sufficient inter-story deformation capacity. Extensive research has been conducted on the static and seismic performances of TRC columns. However, little attention has been paid to the structural system containing TRC columns. To overcome this shortcoming, an experimental study on the seismic behavior of circular tubed reinforced concrete (CTRC) column to steel beam frames (referred as “CTRC frames”) is described first in this study. Based on the previous studies on CTRC columns and joints, two double-bay two-story CTRC frames of 1/2 scale were designed and tested under quasi-static loading: one frame with stronger flexural strength in columns than the beams and the other frame is the opposite. The test results indicated that although the frame failed in column plastic hinge mode had the ductility coefficient of 3.56, a weak story with the maximum story drift ratio of 1/18 formed in this frame, which increased the collapse risk of the overall structure. Therefore, considering the unfavorable deformation mode, the column plastic hinge mode should be avoided in practical designs; and the control of frame deformation modes should be considered when proposing a suitable column-beam strength ratio for CTRC frames. A fiber-based element model using OpenSees software was developed, which showed a good agreement with the test results. Utilizing the numerical model, the affecting parameters to the hysteretic behavior of CTRC frames, such as the axial load ratio, concrete compressive strength, and column-beam strength ratio, were further investigated.

Sealing Behavior in Transcatheter Bicuspid and Tricuspid Aortic Valves Replacement Through Patient-Specific Computational Modeling.

Background: Patient-specific computer simulation of transcatheter aortic valve replacement (TAVR) can provide unique insights in device-patient interaction.Aims: This study was to compare transcatheter aortic valve sealing behavior in patients with bicuspid aortic valves (BAV) and tricuspid aortic valves (TAV) through patient-specific computational modeling.Methods: Patient-specific computer simulation was retrospectively performed with FEops HEARTguide for TAVR patients. Simulation output was compared with postprocedural computed tomography and echocardiography to validate the accuracy. Skirt malapposition was defined by a distance larger than 1 mm based on the predicted device-patient interaction by quantifying the distance between the transcatheter heart valve (THV) skirt and the surrounding anatomical regions.Results: In total, 43 patients were included in the study. Predicted and observed THV frame deformation showed good correlation (R2 ≥ 0.90) for all analyzed measurements (maximum diameter, minimum diameter, area, and perimeter). The amount of predicted THV skirt malapposition was strongly linked with the echocardiographic grading of paravalvular leakage (PVL). More THV skirt malapposition was observed for BAV cases when compared to TAV cases (22.7 vs. 15.5%, p < 0.05). A detailed analysis of skirt malapposition showed a higher degree of malapposition in the interleaflet triangles section for BAV cases as compared to TAV patients (11.1 vs. 5.8%, p < 0.05).Conclusions: Patient-specific computer simulation of TAVR can accurately predict the behavior of the Venus A-valve. BAV patients are associated with more malapposition of the THV skirt as compared to TAV patients, and this is mainly driven by more malapposition in the interleaflet triangle region.

Studi Deformasi Rangka Konveyor Batubara dengan Metode Survei Terestris

One of the mining activities, especially coal mining, the transfer of material onto ships generally uses conveyors. Conveyors have certain maximum limits for transporting and moving material. In a long period of time and continuous use, the conveyor can be deformed, both vertically and horizontally. The part of the conveyor that allows deformation is the frame that plays a role in supporting the material during the transportation process. This study aims to identify and analyze changes in the position of the conveyor frame through the terrestrial survey method with electronic instruments. The initial data used are benchmarks or tie points in the field whose coordinates are known as the basis for determining the coordinates of control points on the conveyor frame. Observations of the conveyor frame are carried out twice in order to know the position before transportation and after transportation. Observation data processing used Terramodel 10.4 software, and tabular and graphical data visualization using Microsoft Excel. From the observation data processing and conveyor frame deformation analysis, it is concluded that the terrestrial survey method can be applied to observe the conveyor frame deformation. This technique is also able to prove the presence of deformation in the conveyor rate through the shift value, both vertically and horizontally. The vertical position change is obtained from the elevation (Z) component, while the horizontal position change is obtained from the X and Y coordinate axis components. For accuracy the resulting shift value is in millimeters. Keywords : coal, deformation, conveyor, positioning, terrestrial

Structural Analysis of Chassis Frame Using CFRP and ANSYS Software

Abstract: Automotive chassis is an important part of an automobile. The chassis serves as a frame work for supporting the body and different parts of the automobile. The chassis frame has to withstand the stresses developed within a limit. Along with strength, an important consideration in chassis design is to have adequate bending stiffness for better handling characteristics. So, strength and stiffness are two important criteria for the design of the chassis. This work is aimed at work performed towards the static structural analysis of the automobile chassis in which study of the stresses developed and deformation of chassis frame of a truck has been done . The chassis is modelled in SolidWorks and finite element analysis has been done in ANSYS. a comparison of current conventional steel chassis structural Steel and Aluminum and CFRP chassis in terms of deflection and stresses must be made in order to select the best one. A discussion and analysis is also done which gives insight on various effects of unidirectional fiber orientations in the chassis on strength and stiffness. Keyword: ANSYS, SolidWorks, chassis, strength, stiffness, structural analysis.

Experimental and numerical study on collapse modes of single span steel portal frames under fire

This paper presents experimental and numerical investigations on the collapse modes of single span steel portal frames exposed to fire. A fire test on a scaled-down single span steel portal frame is conducted and measurements of deformation and collapse mode of the test frame are used to validate the numerical model for simulating the behavior of the single span steel portal frames subjected to fire. Four collapse modes of the portal frames, column lateral collapse, column buckling collapse, overall inward collapse and overall outward collapse, are revealed through parametric studies with the validated numerical model. The effects of heating conditions, stiffness of column base, temperature gradient, fire protection, load ratio, span-height ratio and column spacing on collapse modes of single span steel portal frames in fire are obtained. It is found that heating conditions, stiffness of column base and load ratio have a great impact on the portal frame collapse modes while temperature gradient and fire protection mainly affect the column collapse modes. The findings of this study lay the foundation for early-warning of fire-induced collapse of single span steel portal frames.

REGULARITIES OF THE LINING STRESS-STRAIN STATE DURING OF THE PYLON METRO STATION CONSTRUCTION

Purpose. Perform numerical analysis of the station structure. Take into account in the process of mathematical modeling the process of construction of station tunnels of a three-vaulted station. Obtain the regularities of the stress-strain state of the linings, which is influenced by the processes of soil excavation and lining construction. Methodology. To achieve this goal, a series of numerical calculations of models of the deep contour interval metro pylon station was performed. Three finite-element models have been developed, which reflect the stages of construction of a three-vaulted pylon station. Numerical analysis was performed on the basis of the finite element method, implemented in the calculation complex Lira for Windows. Modeling of the stress-strain state of the station tunnel linings and the soil massif was performed using rectangular, universal quadrangular and triangular finite elements, which take into account the special properties of the soil massif. Station tunnel linings are modeled by means of rod finite elements. Findings. Isofields of the stress-strain state in finite-element models reflecting the stages of construction are obtained. The vertical displacements and horizontal stresses that are characteristic of a three-vaulted pylon station are analyzed. The analysis of horizontal stresses proved that at the stage of opening of the middle tunnel the scheme of pylon operation is rather disadvantageous. The analysis of bending moments and normal forces was also carried out and the asymmetry of their distribution was noted. Originality. Based on the obtained patterns of distribution of stress-strain state and force factors, it is proved that numerical analysis of the station structure during construction is necessary to take measures to prevent or reduce deformation of frames that are in unfavorable conditions. Practical value. In the course of research, the regularities of changes in stresses, displacements, bending moments and normal forces in the models of the pylon station, which reflect the sequence of its construction, were obtained.

Influence of hot isostatic pressing on microstructure, properties and deformability of selective laser melting TC4 alloy

The influence of different hot isostatic pressing regimes on microstructure, phase constitution, microhardness, tensile properties and deformability of TC4 alloy fabricated by selective laser melting (SLM) technology was studied. The results show that the microstructure of SLM TC4 alloy is composed of acicular martensite α’ phase, and the sample exhibits high microhardness and strength, but low plasticity. After hot isostatic pressing, acicular martensite α’ phase transforms into α+β phase, and with the increase of hot isostatic pressing temperature and duration, α phase with coarse lath is gradually refined, and the proportion of α phase is gradually reduced. Because of the change of phase constitution in SLM TC4 alloy after hot isostatic pressing, the grain refinement strengthening is weakened, the density of dislocation is reduced, so that both microhardness and tensile strength are decreased by around 20%, the elongation is increased by more than about 70%, even over 100%, compared with as-deposited TC4 alloy. When the hot isostatic pressing regime is 940 °C/3 h/150 MPa, the tensile strength and the elongation achieve optimal match, which are about 890 MPa and around 14.0% in both directions. The fracture mechanism of alloy after 940 °C/3 h/150 MPa HIP is dultile fracture. Hot isostatic pressing causes concave deformation of SLM TC4 alloy thin-walled frames, and the deformation degree increases with the increase of temperature.

Elastic response of wire frame glasses. I. Two dimensional model.

We study the elastic response of concentrated suspensions of rigid wire frame particles to a step strain. These particles are constructed from infinitely thin, rigid rods of length L. We specifically compare straight rod-like particles to bent and branched wire frames. In dense suspensions, the wire frames are frozen in a disordered state by the topological entanglements between their arms. We present a simple, geometric method to find the scaling of the elastic stress with concentration in these glassy systems. We apply this method to a simple 2D model system where a test particle is placed on a plane and constrained by a random distribution of points with number density ν. Two striking differences between wire frame and rod suspensions are found: (1) The linear elasticity per particle for wire frames is very large, scaling like ν2L4, whereas for rods, it is much smaller and independent of concentration. (2) Rods always shear thin but wire frames shear harden for concentrations less than ∼K/kBTL4, where K is the bending modulus of the particles. The deformation of wire frames is found to be important even for small strains, with the proportion of deformed particles at a particular strain, γ, being given by (νL2)2γ2. Our results agree well with simple numerical calculations for the 2D system.

Textural insights into the significance of ophiolitic chromitites, with special reference to Oman

This paper analyses the process and depth of formation of chromite crystals occasionally including ultrahigh pressure (UHP) minerals, recovered from some investigated ophiolites. We present direct microstructural evidence for crystallization of chromite ores from the Semail ophiolite, in place they are exposed. Similar crystal preferred orientation in olivine-rich layers and in septa from chromite layers indicate deformation of the olivine solid frame by dislocation creep at high temperature, synchronous with the crystallization of chromite. The preservation of the olivine framework throughout the development of joined chromite grains suggests that chromite replaced olivine. Chromite grains crystallized from a melt circulating in an open-system, stress-bearing network of dunitic aggregate, controlled by the olivine high-T slip system. The misorientation of joined crystals at grain boundaries define the ratio of twin vs. random boundaries that were closed to vs. open to fluid circulation, respectively, suggesting that chromite layers may represent planes of channelized melt circulation. The relationship of chromite deposits to ridge tectonics structures suggests that Cr-bearing melt was produced at the transition from an active spreading ridge to deep mantle shear zones acting as possible source of hydration. The occurrence of potential UHP inclusions in chromite crystals is assigned to continental contamination of melts ascending through the Arabian margin.

Numerical Simulation of Casting Deformation and Stress of A356 Aluminum Alloy Thin-Walled Frame Casting

One of the main reasons for the scrap of cast thin-wall frame aluminum alloy castings is deformation and cracking. It is an effective method for solving the problem by predicting the distribution of casting stress, clarifying the size of the deformation and the location of the crack, and taking necessary measures in the process. This paper uses the ProCAST software to simulate the thermal stress coupling of A356 thin-walled frame castings, analyzes the influence of pouring temperature, pouring speed and mold temperature on the stress field distribution of castings, predicts the hot cracking trend and deformation, and optimizes Casting process..

Constantin Carathéodory axiomatic approach and Grigory Perelman thermodynamics for geometric flows and cosmological solitonic solutions

We elaborate on statistical thermodynamics models of relativistic geometric flows as generalisations of G. Perelman and R. Hamilton theory centred around C. Carath\'{e}odory axiomatic approach to thermodynamics with Pfaffian differential equations. The anholonomic frame deformation method, AFDM, for constructing generic off--diagonal and locally anisotropic cosmological solitonic solutions in the theory of relativistic geometric flows and general relativity is developed. We conclude that such solutions can not be described in terms of the Hawking--Bekenstein thermodynamics for hypersurface, holographic, (anti) de Sitter and similar configurations. The geometric thermodynamic values are defined and computed for nonholonomic Ricci flows, (modified) Einstein equations, and new classes of locally anisotropic cosmological solutions encoding solitonic hierarchies.

Decoupling and Integrability of Nonassociative Vacuum Phase Space Gravitational Equations With Star and R‐flux Parametric Deformations

AbstractWe prove that nonassociative star deformed vacuum Einstein equations can be decoupled and integrated in certain general forms on phase spaces involving real R‐flux terms induced as parametric corrections on base Lorentz manifold spacetimes. The geometric constructions are elaborated with parametric (on respective Planck, ℏ, and string, , constants) and nonholonomic dyadic decompositions of fundamental geometric and physical objects. This is our second partner work on elaborating nonassociative geometric and gravity theories with symmetric and nonsymmetric metrics, (non) linear connections, star deformations defined by generalized Moyal‐Weyl products, endowed with quasi‐Hopf algebra, or other type algebraic and geometric structures, and all adapted to nonholonomic distributions and frames. We construct exact and parametric solutions for nonassociative vacuum configurations (with nontrivial or effective cosmological constants) defined by star deformed generic off‐diagonal (non) symmetric metrics and (generalized) nonlinear and linear connections. The coefficients of geometric objects defining such solutions are determined by respective classes of generating and integration functions and constants and may depend on all phase space coordinates [spacetime ones, ; and momentum like variables, )]. Quasi‐stationary configurations are stated by solutions with spacetime Killing symmetry on a time like vector but with possible dependencies on momentum like coordinates on star deformed phase spaces. This geometric techniques of decoupling and integrating nonlinear systems of physically important partial differential equations (the anholonomic frame and connection deformation method, AFCDM) is applied in our partner works for constructing nonassociative and locally anisotropic generalizations of black hole and cosmological solutions and elaborating geometric flow evolution and classical and quantum information theories.

Crash Test Analysis Of Bumpers Ofautomobiles Using Ls-Dyna

This article deals with calculations of deformation and failure of the bumpers of vehicles at different speeds against different obstacles. The main aim of bumpers is to absorb the impact energy in the form of stain energy and efficiently transfer it to the chassis to avoid permanent deformation of the whole frame of any motor vehicle. Different materials have been tried out with and without supporting structures (Ribs) which are known to increase the overall strength of the bumpers while keeping the weight to a minimum. In this experiment, 3 metals namely Sheet Iron, Aluminum and Titanium of varying thickness. Using LD-DYNA 108 cases were implemented. If the component passes the test, the Factor of Safety, Max Stress and the Trends in Variation of these parameters were calculated, the Max Energy Absorbed, Transmitted, the Time required for Failure are extrapolated from the data. Comparisons are drawn between failure, with and without support structures. In the end, overall effectiveness of the support structures in enhancing the load transfer, absorbing strain energy and increasing factor of safety while keeping the mass in check.

EXPERIMENTAL VERIFICATION OF CONSTRUCTIVE SOLUTION OF A NEW TYPE FRAMEWORK

Experimental verification is an integral part of the study for both new designs and new materials and technologies. To assess the features of deformation of the lightweight frame, a series of tests using the method of hydrostatic loading, developed at the Department of Building Structures O.M. Beketov national university of urban economy in Kharkiv. A fragment of a monolithic reinforced concrete frame with a floor slab with a span of 6.0 m and a thickness of 500 mm (thickness of both claddings 100 mm, liner thickness 300 mm) was selected as the object of study. The purpose of the study is to assess the deformability of lightweight frame structures. The tests were implemented under the action of short-term and long-term evenly distributed loads, and were carried out in accordance with the method of hydraulic tests of plates and shells on the basis of the requirements of DSTU B B.2.6-7: 95. For research the research method based on hydrostatic loading of object when loading is set by weight of water is used, and its size is regulated by height of a water column. To carry out the described test procedure on the mezzanine floor of the seventh floor was assembled inventory pool of formwork panels with dimensions in terms of 5.2x2.8 m and a board height of 1.15 m. To register the measured displacements, sensors are supplied to the object under study, which allow to establish the characteristics of the stress-strain state of the object of study. Use of this method, in comparison with other existing, allows to define durability and deformability of various full-scale designs at short-term and long loading without their destruction and a stop of production process. The obtained results of field testing of a fragment of a lightweight frame indicate that the nature of the deformation of the floor under load correlates with the results of similar studies that have been repeatedly conducted for the frames of buildings with load-bearing elements with a continuous cross section.

Seismic response of steel multi-tiered eccentrically braced frames

Steel eccentrically braced frames (EBFs) are commonly used as a lateral load-resisting system, in particular in high seismic regions, due to their high ductility, stable and reliable yielding mechanism, and architectural versatility as compared to concentrically braced frames. This article presents the use of EBFs in tall single-storey structures where multiple braced panels with intermediate links are stacked along the frame height, which is referred to as multi-tiered eccentrically braced frames (MT-EBFs). A set of nine frames having different heights, number of tiers, relative tier heights, and brace-to-beam connections are designed in accordance with the Canadian steel design standard. The seismic performance of the frames is then examined using nonlinear response history analysis (NLRHA) with an emphasis on the stability of intermediate links and columns as well as in-plane tier drift and column moment demands. As potential solutions to this problem, alternative intermediate link designs are examined and their seismic performance is presented. The results show that lateral frame deformations tend to non-uniformly distribute between tiers due to uneven link shear yielding, which impose large moments on outer beams and in-plane and out-of-plane bending demands on the columns, which in some cases leads to column buckling. The unbraced intermediate links are found to be prone to lateral out-of-plane buckling. Alternative design strategies except MT-EBFs with laterally-braced links did not appreciably improve link and column stability. Intermediate link stability and column flexural demands shall be considered in seismic design of MT-EBFs.

Finite Element Analysis of Deformation Effect of Concrete Filled Steel Tubular Composite Frame under High Temperature

The research on the mechanical characteristics of concrete-filled steel tubular composite frame under high temperature is one of the hot topics. In this paper, through the finite element simulation software, the failure characteristics of the deformation of concrete-filled steel tubular composite frame and the simulation results of the deformation effect of concrete-filled steel tubular composite frame structure are analyzed, including the effect of each component in different temperature fields, different structural fields and various coupling fields, the redistribution and change of the local plastic region of the component under high temperature, and the change of the local plastic region of the component under high temperature. The comparative analysis of the flexural effect of two-story two span concrete-filled steel tubular composite frame under different fire positions shows that: with the rising of fire time, the vertical displacement is also increasing, the scope of local plastic area is expanding, the deflection redistribution is obvious, and finally the mechanism is formed, and the failure occurs. The deformation effect of condition 1 changes more than that of condition 2, which indicates that the two-story two span steel tubular composite frame has a large deformation effect. The fire resistance of concrete-filled tubular composite frame is better under the condition of full section fire. The research results can provide reference value for strengthening and repairing of concrete-filled steel tubular composite frame under high temperature.