Non-linear analysis of unbolted base plates by the FEM and experimental validation

• Published in: Thin-walled structures Vol. 44; no. 5; pp. 529 - 541
• Main Authors: DEL COZ DIAZ, J. J, GARCIA NIETO, P. J, BETEGON BIEMPICA, C, FERNANDEZ ROUGET, G
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.05.2006; New York, NY Elsevier Science
• Subjects: Applied sciences; Base plates; Building structure; Buildings. Public works; Construction (buildings and works); Contact problems; Exact sciences and technology; Finite element modeling; Fundamental areas of phenomenology (including applications); Inelasticity (thermoplasticity, viscoplasticity...); Large displacements; Mechanical contact (friction...); Numerical methods; Physics; Plasticity; Solid mechanics; Static elasticity (thermoelasticity...); Structural and continuum mechanics; Base plates; Large displacements; Contact problems; Finite element modeling; Numerical methods; Plasticity; Metallic structure; Point contact; Non linear material; Displacement(deformation); Modeling; Finite element method; Inelasticity; Column; Integral equation; Two phase medium; Buckling; Civil engineering; Lateral load; Frame construction; Mechanical properties; Large displacement; Experimental study; Storage rack; Contact surface; Plate; Friction; Non linear effect; Structural analysis
• ISSN: 0263-8231; 1879-3223
• DOI: 10.1016/j.tws.2006.04.008

Unbolted base plates are often used in civil engineering as structural connections in storage racks construction. The aim of this work is to describe the development of a numerical model to simulate accurately the connection between columns and foundation in metallic structures, which constitute any frame in automated storage systems. In this way, the bending stiffness of the column can be modeled in the analysis of these structures, in order to approach the real behavior in service, and these values can be included in linear beams of structural analysis programs, such as ESCAL3D [del Coz Diaz JJ, Ordieres Mere B, Siare Dominguez FJ, Bello García A, Felgueros Fernández D. J Constr Res 1998; 46:273–5]. In this study, a non-linear structural behavior of the model occurs due to the changing status of the contact surfaces and point-to-point contacts, the geometric non-linearities of the model and the material non-linearities, such as plasticity and surface friction. The finite element method is a general technique for numerical solution of differential and integral equations in science and engineering. Thus the finite element approach has been carried out in two phases. Firstly, a pre-buckling analysis has been accomplished and secondly, the above-mentioned non-linear analysis has been performed, updating the geometry of the finite element model to the deformed configuration for the first mode buckling. A total of four load cases were analyzed, with different compressive load and imposed lateral displacement. In order to validate the results some experimental models were tested to compare with the numerical model, so that a good agreement and better correlations were obtained between both.