Course detail
Nonlinear mechanics
FAST-CD56Acad. year: 2009/2010
Types and sources of nonlinear behavior of structures. New definition of stress and strain measures that is necessary for geometrical nonlinear analysis of structures. Principles of numerical solution of nonlinear problems (Newton-Raphson, modified Newton-Rapshon, arc length). Post critical analysis of structures. Linear and nonlinear buckling. Application of the presented theory for the solution of particular nonlinear problems by a FEM program.
Language of instruction
Number of ECTS credits
Mode of study
Guarantor
Department
Learning outcomes of the course unit
Prerequisites
Fundamentals of numerical mathematics. Infinitesimal calculus.
Co-requisites
Planned learning activities and teaching methods
Assesment methods and criteria linked to learning outcomes
Course curriculum
2.Strain measures (Green-Lagrange, Euler-Almansi, engineering, logarithmic), their behavior in large strain and large rotation. Stress measures (Cauchy, 1. Piola-Kirchhoff, 2. Piola-Kirchhoff, Biot). Energeticaly conjugate stress and strain measures.
3.Tangent stiffness matrix, Material stiffness, Geometrical stiffness. Influence of nonlinear members of the strain tensor. Newton-Raphson method. Calculation of unbalanced forces.
4.Modified Newton-Raphson method. Postcritical analysis. Deformation control. Arc length method
5.Linear and nonlinear buckling. Von Mises truss, snap through. Physical nonlinearity (supports, beams, concrete, subsoil).
6.Types of materials, introduction into constitutive material models. Linear and nonlinear fracture mechanics. Fracture mechanical material parameters.
7.Problem of strain localization, false sensitivity on the mesh. Restriction of localization. Crack band model. Nonlocal continuum mechanics.
8.Constitutive equations for concrete and other quasi-fragile materials. Fracture-plastic model. Mircroplane model.
9.Influence of size to bearing capacity (size effect). Energetical and statistical causes. Analysis of the influence of size on strength in tension in bending.
10.Presentation of modeling by a software on nonlinear fracture mechanics. Examples of applications. Mechanics of damane.
Work placements
Aims
Specification of controlled education, way of implementation and compensation for absences
Recommended optional programme components
Prerequisites and corequisites
Basic literature
Servít, R., Drahoňovský, Z., Šejnoha, J. Kufner, V.: Teorie pružnosti a plasticity II. STNL/ALFA Praha, 1984.
Recommended reading
Desai, C. S, Siriwardane, H. J.: Constitutive Laws for Engineering Materials. Prentice - Hall, 1984.
Classification of course in study plans