Lecture Details :
Dynamics of Ocean Structures by Dr. Srinivasan Chandrasekaran, Department of Ocean Engineering, IIT Madras. For more details on NPTEL visit http://nptel.iitm.ac.in
Course Description :
Introduction to different types of ocean structures - Development of structural forms for deep and ultra-deep waters - Environmental forces - structural action of ocean structures - fluid-structure interaction - Introduction to structural dynamics - Characteristics of single degree-of-freedom model - Methods of writing equation of motion - comparison of methods - Free and forced vibration of single degree-of-freedom systems - Undamped and damped systems - Formulation of equation of motion - examples - Coulomb damping - comparison of damped and undamped forced vibration - response build up - Numerical problems in single degree-of-freedom systems - Two degrees-of-freedom systems.
Formulation of equation of motion - Eigenvalues and eigenvectors - Orthogonality of modes - Study of multi degrees-of-freedom systems - Equations of motion - Natural frequencies and mode shapes - Stodla, Rayleigh-Ritz and influence coefficient methods, Dunkerley - Matrix methods for dynamic analysis - Eigen solution - Modal analysis - Structural action of offshore structures - Types of offshore structures based on the geometric form - Development of structural form for deep waters - Fluid-structure interaction - Dynamic analysis of offshore jacket platforms - steps of analysis using software - Dynamic analysis of articulated towers - Iterative frequency domain - Multi-legged articulated towers - Response control of multi-legged articulated towers using tuned mass dampers - Experimental and analytical studies on MLAT - Development of Tension Leg Platforms and geometric optimization - Dynamic analyses of TLPs
Development of Mass, stiffness and damping matrices of TLP from first principles - Dynamic analysis methodology of offshore structures under earthquakes - TLPs under seismic excitation - Development of new generation offshore structures - Buoyant Leg Structures and offshore triceratops - Numerical modeling of offshore triceratops using software - Comparison of experimental, analytical and numerical studies on offshore triceratops - Estimate of damping: Classical damping, Rayleigh and Caughey - Damping by mode superposition - Analytical technique to solve equation of motion using in Newmarks Beta method - Introduction to stochastic dynamics of ocean structures - Random environmental processes - Stationary process - Response spectrum - Narrow band process - Return period - Fatigue prediction - Modal response method - Modal mass contribution - Missing mass correction, Example problems - Duhamel's integrals