Elastic Stability of Structures

ABOUT THE COURSE: A thorough understanding on structural stability is essential to structural engineers whose job is to design safe and economic structures. In a structure, a small change in compressive load could cause a large variation in displacement. If this change in displacement is large enough in a critical member of the structure, a local or member instability could lead to collapse of the entire structure. Instability failures is catastrophic.This course explains how and under what loading condition, a structure passes from a stable state to unstable state. Different structural members and systems are analyzed for their stability. This also includes how theory translates into design methods implemented in design guidelines. All major international standard specifications include provisions based on stability theory. Attention is especially focused on metal structures. Compared to structures designed using other construction materials, metal structures rely to a greater extent on stability limit states.INTENDED AUDIENCE: Civil & Structural Engineering/ Mechanical Engineering/Aerospace Engineering/ Naval Structures studentsPREREQUISITES:Mechanics of SolidINDUSTRY SUPPORT: All Structural Engineering Industries. All Construction Industries like L&T, Indian Space Research Organisation (ISRO), Defence Research and Development Organisation(DRDO) , GE Mechanics and Design, National Aerospace Laboratory (NAL),Aeronautical Development Establishment(ADE), Aaerospace firms like Boeing, Airbus etc., Composite manufacturing industries.

Week 1: Fundamental principles for elastic stability, Approximate methods in elasticity Week 2:Variational method in elastic problems, Principle of minimum potential energy Week 3:Stability of rigid body systems for one-degree-of-freedom model by using different approaches, Two-degree-of-freedom structural model for stability analysis, Snap-through model and model with imperfect geometry Week 4:Eigenvalue problems for elastic buckling of columns, Buckling of columns with different end conditions, Buckling of column with imperfection and eccentric loading Week 5:Buckling of column with imperfection and eccentric loading (Contd.), Elastically supported columns, Basic equation for stability of beam-columns Week 6:Analysis of beam-columns with different loading conditions, Stability analysis of frames, Finite element frame work for stability analysis of frames Week 7:Stability analysis of continuous beam-columns, Energy based methods for elastic buckling analysis, Buckling of bars on an elastic foundation, Buckling of bars with distributed axial load Week 8:Torsion of thin walled open cross section, Torsional buckling, Torsional-flexural buckling of thin walled columns Week 9:Buckling of uniformly compressed circular arch, Buckling of circular rings under uniform external pressure Week 10:Governing differential equation of plate buckling, Buckling load of thin Rectangular Plates by energy method Week 11:Symmetrical buckling of cylindrical shell, Governing differential equation of cylindrical shell buckling, Buckling load of cylindrical shell by energy method Week 12:Inelastic stability analysis of column, Eccentrically loaded inelastic stability analysis of column