A Numerical and Closed-Form Analytical Solution of the Global Buckling Critical Load of Tall Buildings Including Soil Flexibility: Timoshenko Beam

PurposeThe global buckling critical load ratio is a paramount parameter dictating the overall performance of tall buildings, yet its exploration has been notably lacking in the existing literature. This study addresses this gap by delivering a comprehensive theoretical investigation, along with presenting both analytical and numerical methods for computing the global buckling critical load ratio.MethodologyThese methods are designed to accommodate uniform and non-uniform tall buildings, taking into account diverse vertical load profiles, including considerations for soil flexibility. In this endeavor, a continuous Timoshenko-type model is employed, characterized by flexural and shear stiffness parameters defined by a dimensionless factor. To enhance the versatility of the analysis, an analytical solution method has been devised for uniform tall buildings. In contrast, a numerical solution method has been formulated to address the intricacies posed by tall structures exhibiting variable properties along their height, including soil flexibility.Results and ConclusionsNotably, our investigation uncovers that the rotational flexibility of the underlying soil significantly influences the eigenvalues. Furthermore, the parametric analyses carried out in this study underscore the exceptional convergence achieved by the proposed solution methods and highlight the superiority of the continuous model, enabling the execution of parametric studies with minimal computational expenses.