Abstract
This paper presents a numerical model for buckling analysis of slender piles, such as micropiles. The model incorporates geometric nonlinearities to provide enhanced accuracy and a more comprehensive representation of pile buckling behavior. Specifically, the pile is represented using geometrically nonlinear beams with the von Karman deformation measure. The lateral support provided by the surrounding soil is modeled using the spring approach, with the spring stiffness determined according to the undrained shear strength of the soil. The numerical model is tested across a wide range of pile slenderness ratios and undrained shear strengths of the surrounding soil. The numerical results are validated against analytical solutions. Furthermore, the influence of various pile bottom end boundary conditions on the critical buckling force is investigated. The implications of the obtained results are thoroughly discussed.
Key Words
buckling; geometric nonlinearities; micropile; pile; spring; stiffness; undrained shear strength; von Karman; weak soil
Address
Emina Hajdo: Faculty of Civil Engineering, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina
Emina Hadzalic: Faculty of Civil Engineering, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina
Adnan Ibrahimbegovic: Université de Technologie de Compiègne-Alliance Sorbonne Université, Centre de Recherche, 60200 Compiègne, France
Abstract
This study aims to develop a new model to obtain the minimum area in circular isolated footings with eccentric column taking into account that the surface in contact with the ground works partially in compression, i.e., a part of the contact area of the footing is subject to compression and the other there is no pressure (pressure zero). The new model is formulated from a mathematical approach based on a minimum area, and it is developed by integration to obtain the axial load "P", moment around the X axis "Mx" and moment around the Y axis "My" in function of omax (available allowable soil pressure) R (radius of the circular footing), a (angle of inclination where the resultant moment appears), y0 (distance from the center of the footing to the neutral axis measured on the axis where the resultant moment appears). The normal practice in structural engineering is to use the trial and error procedure to obtain the radius and area of the circular footing, and other engineers determine the radius and area of circular footing under biaxial bending supported on elastic soils, but considering a concentric column and the contact area with the ground works completely in compression. Three numerical problems are given to determine the lowest area for circular footings under biaxial bending. Example 1: Column concentric. Example 2: Column eccentric in the direction of the X axis to 1.50 m. Example 3: Column eccentric in the direction of the X axis to 1.50 m and in the direction of the Y axis to 1.50 m. The new model shows a great saving compared to the current model of 44.27% in Example 1, 50.90% in Example 2, 65.04% in Example 3. In this way, the new minimum area model for circular footings will be of great help to engineers when the column is located on the center or edge of the footing.
Key Words
axial load; circular isolated footings; minimum area; moment around the X axis; moment around the Y axis; surface in contact with the ground works partially in compression
Address
Inocencio Luévanos-Soto: Instituto de Investigaciones Multidisciplinaria, Universidad Autónoma de Coahuila, Blvd. Revolución No, 151 Ote, CP 27000, Torreón, Coahuila, México
Arnulfo Luévanos-Rojas, Victor Manuel Moreno-Landeros: Facultad de Ingeniería, Ciencias y Arquitectura, Universidad Juárez del Estado de Durango, Av. Universidad S/N, Fracc. Filadelfia, CP 35010, Gómez Palacio, Durango, México
Griselda Santiago-Hurtado: Facultad de Ingeniería Civil, Universidad Autónoma de Coahuila, CP 27276, Torreón, Coahuila, México
Abstract
By introducing optimization algorithms into the machining process, product quality can be improved, time saved, and costs reduced. The cutting speed and feed can be handled by the turning machine. The approach of optimizing is used to manage pyrotechnics, Lawler's, greedy, bacterial colony, elephant herding, ant lion, spiral, auction, and pattern search for these ten odd ways. Ten artificial optimization methodologies were used to investigate the time and cost of a turning machine. It has been discovered how to create the optimal turning machine procedure. The best solution approach for the turning machine process problem is found, and the results are verified using ANSYS.
Key Words
ANSYS; optimization techniques; simulation; tuning machine process
Address
T. Jagan: Department of Mathematics, Karunya Institute of Technology and Sciences, Coimbatore, Tamil Nadu, 641114, India; Department of Mathematics, KG College of Arts and Science, Coimbatore, Tamil Nadu, 641035, India
S. Elizabeth Amudhini Stephen: Department of Mathematics, Karunya Institute of Technology and Sciences, Coimbatore, Tamil Nadu, 641114, India
Abstract
In the present work, a microelogated thermoelastic model based on Lord-Shulman (1967) and Green-Lindsay (1972) theories of thermoelasticity has been constructed. The governing equations for the simulated model are converted into two-dimensional case and made dimensionless for further simplification. Laplace and Hankel transforms followed by eigen value approach has been employed to solve the problem. The use of eigen value approach has the advantage of finding the solution of governing equations in matrix form notations. This approach is straight forward and convenient for numerical computation and avoids the complicate nature of the problem. The components of displacement, stress and temperature distribution are obtained in the transformed domain. Numerical inversion techniques have been used to invert the resulting quantities in the physical domain. Graphical representation of the resulting quantities for describing the effect of microelongation are presented. A special case is also deduced from the present investigation. The problem find application in many engineering problems like thickwalled pressure vessel such as a nuclear containment vessel, a cylindrical roller etc.
Key Words
eigen value approach; Laplace and Hankel transforms; microelongation; thermoelasticity
Address
Rajneesh Kumar: Department of Mathematics, Kurukshetra University, Kurukshetra, Haryana, India
Aseem Miglani, Ravinder Kumar: Department of Mathematics, Ch. Devi Lal University, Sirsa, Haryana, India
Abstract
The paper studies the influence of the fluid flow velocity and flow direction in the initial state on the dispersion of the axisymmetric waves propagating in the inhomogeneously pre-stressed hollow cylinder containing this fluid. The corresponding eigenvalue problem is formulated within the scope of the three-dimensional linearized theory of elastic waves in bodies with initial stresses, and with linearized Euler equations for the inviscid compressible fluid. The discrete-analytical solution method is employed, and analytical expressions of the sought values are derived from the solution to the corresponding field equations by employing the discrete-analytical method. The dispersion equation is obtained using these expressions and boundary and related compatibility conditions. Numerical results related to the action of the fluid flow velocity and flow direction on the influence of the inhomogeneous initial stresses on the dispersion curves in the zeroth and first modes are presented and discussed. As a result of the analyses of the numerical results, it is established how the fluid flow velocity and flow direction act on the magnitude of the influence of the initial inhomogeneous stresses on the wave propagation velocity in the cylinder containing the fluid.
Address
Surkay D. Akbarov: Department of Mechanical Engineering, Faculty of Mechanical Engineering, Yildiz Technical University, Yildiz Campus, 34349, Besiktas, Istanbul-Turkey; Institute of Mathematics and Mechanics of Science and Education Ministry Republic of Azerbaijan, Baku, Azerbaijan
Jamila N. Imamaliyeva, Reyhan S. Akbarli: Azerbaijan University of Architecture and Construction, Baku, Azerbaijan
