Influence Of Axial Force Research Articles

Development of Analytical Model of Cantilever Hook Performance

With an increase in the use of polymeric materials in commercial products, snap-fits are attracting increased attention as alternatives to other, more traditional, joining methods. The field of snap-fit design is receiving greater attention as an engineering and research activity. Research in this area has focused on the development of performance models for individual features and heuristics for the design of snap-fit assemblies. An improved analytical model for cantilever hook snap-fit features is developed in this study. The modeling approach is a significant improvement over currently available analytical design equations. The model captures the effect of a snap-fit’s catch in causing contact forces to be offset from the beam’s neutral axis. Beam rotation, influence of axial force, and moment components on beam deformation are also incorporated by formulating a set of equations that model the system in its deformed configuration. The equation system is iteratively solved for several such configurations to model insertion and retention processes for snap-fits. The axial force component, which has been hitherto ignored in analytical design equations, is found to have significant effect on predicted snap-fit performance. The design space of cantilever hook features is explored by varying input design parameters. The model shows excellent agreement with experimental results, especially for low and medium retention angle snap-fit features. However, for high retention angle snap-fits, more accurate governing equations are required. Suggestions for possible improvements and future research directions are provided.

Component method extension to steel beam‐to‐beam and beam‐to‐column knee joints under bending and axial forces

Abstract This paper presents an analysis of semi‐rigid beam‐to‐beam end‐plate bolted and beam‐to‐column end‐plate bolted knee joints that are subjected to bending and tension or compression axial force. Usually the influence of axial force on joint rigidity is neglected. According to EC3, the axial load, which is less than 10 % of plastic resistance of the connected member under axial force, may be disregarded in the design of joint. Actually the level of axial forces in joints of structures may be significant and has a significant influence on joint rigidity. One of the most popular practical method permitting the determination of rigidity and strength of joint is the so‐called component method. The extension of the component method for evaluating the influence of bending moment and axial force on the rigidity and strength of the joint are presented in the paper. The numerical results of calculations of rigidity and strength of beam‐to‐beam and beam‐to‐column knee joints are presented in this paper as well.

The optimal control of fracture and stress parameters in a piezoceramic halfspace with cracks

An approach to the determination of the optimal control of fracture and strength parameters in a piezoceramic halfspace with cracks under antiplane deformation conditions is proposed. The distribution over certain part of the halfspace boundary, harmonically changing with time under the influence of axial forces or electric charges is analyzed as a control interaction. The solution of the inverse problem in fracture mechanics is obtained from the solution of the corresponding direct boundary value problem; in this case, the optimization problem is reduced to the momentum problem. The solution of the direct electroelastic problem using the method of the boundary integral equations is obtained. Various control functions permitting to realize the optimal process of control, i.e. the minimal energetic expenses, are given.

Influence of Axial Force in The Intermediate Shaft on the Load Capacity of the Paired Cardan Mechanism

The design of intermediate shaft with axially movablesplined joint must be adapted to the variable position of theshaft axis, i.e. to the change of the joint angle during operation.This design is also used for the reduction of axial forces whichare caused by inaccuracy in the production and assembling ofC(ll·dan mechanisms. The axial force which is generated by frictionof contact swfaces in the splined joint is the function of themagnitude of the transfeJTed torsion moments, splined dimensions,lubrication conditions, and materials used for contactswfaces. It will cause additional bearing loads at cross journalsand in the shaft supports, as well as unallowed vibrations andnoise during operation, thus affecting the safety and lifetime ofthe Cardan mechanism. The theoretical and empirical analysisof Cm·dan mechanisms, which have been studied with andwithout axial forces in the splinedjoint and its effect on durabilityof mechanism elements have been presented.

Free vibrational analysis of axially loaded bending-torsion coupled beams: a dynamic finite element

In this article, a dynamic finite element formulation for the free vibration analysis of axially loaded bending-torsion coupled beams is presented. Based on the Euler–Bernoulli and St. Venant beam theories, the exact solutions of the differential equations governing the uncoupled vibrations of an axially loaded uniform beam are found. Then, employing these solutions as basis functions, the analytical expressions for uncoupled bending and torsional dynamic shape functions are derived. Exploiting the principle of virtual work, together with the variable approximations based on the resulting shape functions, leads to a single frequency dependent element matrix which has both mass and stiffness properties. The application of the theory is demonstrated by an illustrative example of a bending-torsion coupled beam with cantilever end conditions, for which the influence of axial force on the natural frequencies is studied. The correctness of the theory is confirmed by the published results and numerical checks.

8 歯列咬合接触に与える歯への加圧の影響 (第446回 大阪歯科学会例会)

8 歯列咬合接触に与える歯への加圧の影響 (第446回 大阪歯科学会例会)

Influence of axial forces on occlusal contact

Influence of axial forces on occlusal contact

Coupled bending-torsional dynamic stiffness matrix of an axially loaded timoshenko beam element

Analytical expressions for the coupled bending-torsional dynamic stiffness matrix terms of an axially loaded uniform Timoshenko beam element are derived in an exact sense by solving the governing differential equations of motion of the element. The symbolic computing package REDUCE has been used to generate an analytical expression for each of the dynamic stiffness terms in a concise form. For check purposes, numerical values of the dynamic stiffness matrix terms were obtained using the derived explicit expressions as well as by an alternative nonanalytical method based on matrix inversions and matrix multiplications. Stiffnesses obtained from both methods agreed with each other to machine accuracy. Application of the developed theory is discussed with particular reference to an established algorithm. The influence of axial force, shear deformation and rotatory inertia on the natural frequencies of a bending-torsion coupled beam with cantilever end-conditions is demonstrated by numerical results. Such results are not generally available in the literature. Therefore, results obtained by partially restricting the present theory are compared with the existing literature wherever possible. The results indicate that the method is accurate and efficient.

Coupled bending–torsional dynamic stiffness matrix for axially loaded beam elements

AbstractAnalytical expressions for the coupled bending–torsional dynamic stiffness matrix elements of an axially loaded uniform beam element are derived in an exact sense by solving the governing differential equations of motion of the beam. The influence of axial force on the coupled bending–torsional frequencies of a cantilever and hinged–hinged beam of thin‐walled section is demonstrated by numerical results. Application of the developed theory includes coupled bending–torsional frequency and mode calculations of helicopter, turbine and propeller blades, plane and space frames, and grillages consisting of axially loaded beam elements with non‐coincident mass centre and shear centre.

The nonlinear numerical analysis method for frames

This paper gives the direct formulas of stiffness matrixes of two kinds of Kirchhoff nonlinear elements under total-Lagrange coordinate. For the first one, it includes not only the quadric terms of increments of strain and displacement but also the influence of rotations. For the second one, it is simplified and its nonlinear is considered by taking into account the influence of axial force on the equilibrium equation in the linear beam theory.

Generalized eringen problem: influence of axial force on random vibration response of simply supported beam

The Eringen problem—that of a random vibration of a uniform beam simply supported at its ends—is generalized herewith to include the effect of a deterministic axial loading. The beam is excited by a random transverse load represented by a space- and time-wise ideal white noise. A closed-form solution is obtained for the displacement space-time correlation function at zero time lag. It is shown that as the axial load approaches the Euler buckling level, the random displacement response increases indefinitely. For axial loads below this level, the obtained expressions permit explicit evaluation of probabilistic characteristics of the response.

Buckling of bridges with inclined legs

Abstract This paper presents the analytical equations of equilibrium for a nonsymmetrical bridge with inclined legs, using the slope deflection method which is valid when the influence of axial forces on the various parts of the bridge is taken into account. The inclined legs are either pin-jointed or fixed to the ground, while the total loading consists firstly of uniform loads and secondly of a concentrated load imposed at any position of the bridge span. On the basis of these equations, a procedure is developed through which the minimum critical concentrated load is calculated and its corresponding point of action is also determined. This is achieved through the buckling interaction curves and the diagrams of the critical loads which are plotted for each group of dimensionless parameters corresponding to a certain bridge.

A STOCHASTIC CHARACTERIZATION OF THE MACHINE TOOL WORKPIECE SYSTEM IN BTA OEEP HOLE MACHINING Part I: Mathematical Modelling and Analysis

ABSTRACT A three dimensional model of the BTA deep-hole machining system is presented by modelling each of the components separately and later combining to represent the total system. A model for the interaction between the workpiece and the cutting tool is also included. Such a model can determine the response of any component of the machine tool as well as the individual influence on the system performance. Based on this, physical models representing the three working methods in the BTA process can be studied, from which stochastic differential equations are derived to represent the resultant force system on the machine tool A physical model for the stationary workpiece and rotating cutting tool working method is developed. The assumed modes method along with the Lagrange' equation is used to obtain the stochastic differential equation to represent the influence of axial force and torque, in order to obtain the response of the system under the action of the axial force and torque to predict the stabilit...

Seismic analysis of a rotor‐bearing system

AbstractThe seismic analysis of a rotor‐bearing system is presented in the time domain. The governing equations of motion for the rotor are derived including the effects of rotatory inertia, shear deformation, gyroscopic effects, axial force, axial torque, stiffness and damping provided by the lubricants in the bearings, base translation and base rotation. A simple and efficient finite rotor element based on a Galerkin formulation is proposed to model the rotor. The effects of disks and flywheels mounted on the rotor are also included in the analysis. An example problem for a rotor‐bearing system is solved using El Centro earthquake data. Four cases are investigated that will permit one to study the influence of spin, base rotation, comparison between rigid body model and beam model and the influence of axial force and axial torque. The results of the above study show that the gyroscopic effects amplify the response of the rotor‐bearing system. The base rotations of the rotor‐bearing system under seismic excitation contribute significantly to the response.

Influence of axial force on the elastic-plastic bending and springback of a beam

In the industrial forming of metal sheet or plate components by means of a bending operation, a constant problem is the change of shape, or “springback”, of the formed part under the elastic stresses that are released when the forming pressure is removed. For the close-tolerance forming of such components, an accurate means of calculating the springback is of great value, as this enables a corrective allowance to be made when designing and performing the forming operation itself. In the present paper, the influence of axial force on the elastic-plastic bending and springback of a beam is examined. After obtaining the fundamental relationship between the curvature of the beam and the load for the case of pure bending, both the elastic-plastic bending of a cantilever subjected to a concentrated force at its tip and the springback are considered. It is shown that the analysis can be applied to the press-brake bending of strips and the equibiaxial bending of plates.

A method of shakedown analysis of frames and arches

Structures, in general, are subjected to more complex load programs than those considered in the theory of limit analysis. The shakedown theory presents general theorems allowing to estimate does the structure adapt to the given load program or not. On the basis of previous general results [22] the present paper gives an approximate method of analysis of frames and arches of arbitrary solid cross-section in the case when the influence of axial forces on the stress state cannot be neglected. The problem reduces to the linear programming problem. Numerical results for a portal frame and for a circular arch of rectangular cross-section are presented.

A class of complete solutions for bending of perfectly-plastic beams

An approach is developed for determining complete solutions for simply supported rectangular beams composed of a rigid, perfectly-plastic material under the action of distributed surface load. Detailed solutions are given for loading over a central strip in plane strain, and the solutions exhibit a sharp transition from failure in bending to failure by local plastic flow at the Prandtl value of the applied pressure. The influence of axial force is discussed and some complete solutions are developed for bending of simply supported beams in plane stress. Comparisons are made between the exact values of the collapse pressure and the values given by beam theory.

2281 鋼管と鋼管の十字型接合部の研究 : 2.主管軸力のある場合(構造)

2281 鋼管と鋼管の十字型接合部の研究 : 2.主管軸力のある場合(構造)