Scalar: |
(english) A mathematical entity which has a numeric value but no direction (in contrast to a vector). |
Section Modulus: |
(english) A property of a cross sectional shape, which depends on shape, and orientation. Section modulus is usually denoted S, and S = I/c, where I = moment of inertia about an axis through the centroid, and c is the distance from the centroid to the extreme edge of the section. |
Shear: |
(english) An system of internal forces whose resultant is a force acting perpendicular to the longitudinal axis of a structural member or assembly: sometimes called shear force. |
Shear stress: |
(english) Stress acting parallel to an imaginary plane cut through an object. |
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. |
Stability: |
(english) Stability is best defined as the opposite of instability, which is the occurrence of large structural deformations which are not the result of material failure. |
Statically determinate: |
(english) A statically determinate structure is one where there is only one distribution of internal forces and reactions which satisfies equilibrium. In a statically determinate structure, internal forces and reactions can be determined by considering nothing more than equations of equilibrium. |
Statically equivalent: |
(english) Two force systems are statically equivalent when their resultants are equal. Physically, this means that the force systems tend to impart the same motion when applied to an object; note that the distribution of resulting internal forces in the object may be different. |
Statically indeterminate: |
(english) A statically indeterminate structure is one where there is more than one distribution of internal forces and/or reactions which satisfies equilibrium. |