Linear Elastic: |
(english) A force-displacement relationship which is both linear and elastic. For a structure, this means the deformation is proportional to the loading, and deformations disappear on unloading. For a material, the concept is the same except strain substitutes for deformation, and stress substitutes for load. |
Modulus of elasticity: |
(english) The proportional constant between stress and strain for material with linear elastic behavior: calculated as stress divided by strain. Modulus of elasticity can be interpreted as the slope of the stress-strain graph. It is usually denoted as E, sometimes known as Young's Modulus Y, or E-Modulus. |
Normal strain: |
(english) Strain measuring the intensity of deformation along an axis. Normal strain is usually denoted by . Average normal strain between two points is calculated as (Delta L / L), where L is the original distance between the points, and L is the change in that distance. Normal strain is often simply called strain. |
Pin connection: |
(english) In two dimensions, a pin connection restrains two translation degrees of freedom but does not restrain rotation. Since the rotation degree of freedom is unrestrained at a pin connection, it transfers no moment. |
Pin support: |
(english) In two dimensions, a pin support restrains two translation degrees of freedom but does not restrain rotation. When considering reaction forces, a pin support is usually considered to have two force components: one each about the x and y axes respectively. |
Roller support: |
(english) In two dimensions, a roller support restrains one translation degree of freedom. |
Shear strain: |
(english) Strain measuring the intensity of racking in the material. Shear strain is measured as the change in angle of the corners of a small square of material. |
Shear modulus: |
(english) The ratio of shear stress divided by the corresponding shear strain in a linear elastic material. |
Stiffness: |
(english) This is a general term which may be applied to materials or structures. When a force is applied to a structure, there is a displacement in the direction of the force; stiffness is the ratio of the force divided by the displacement. High stiffness means that a large force produces a small displacement. When discussing the stiffness of a material, the concept is the same, except that stress substitutes for force, and strain substitutes for displacement; see modulus of elasticity. |
Strain: |
(english) The intensity of deformation at a point in an object. See normal strain and shear strain. |