The extent of space between two supports of a structure.

The distance between the inner faces of the supports of a span.

The center to center distance between the supports if a span.

An external moment tending to cause part of a structure to rotate or bend, equal to the algebraic sum of the moments about the neutral axis of the section under consideration

An internal moment equal and opposite to a bending moment, generated by a force couple to maintain equilibrium of the section being considered.

The perpendicular distance a spanning member deviates from a true course under transverse loading, increasing with load and span, and decreasing with an increase in the moment of inertia of the section or the modulus of elasticity of the material.

A slight convex curvature Intentionally built into a beam, girder, or truss to compensate for an anticipated deflection.

An Imaginary Line passing through the centroid of the cross section of a beam or other member subject to bending, along which no bending stresses occur.

A combination of compressive and tension stresses developed at a cross section of a structural member to resist a transverse force, having a maximum value at the surface furthest from the neutral axis.

An external shear force at a cross section of a beam or other member subject to bending equal to the algebraic sum of transverse forces on one side of the section.

The shearing stress developed to prevent slippage along longitudinal planes of a beam under transverse loading, equal at any point to the vertical shearing stress at that point.

The shearing stress developed to along a cross-section of a beam to resist transverse shear, having a maximum value at the neutral axis and decreasing nonlinearly toward the outer faces.

The sum of the products of each element of an area and the square of its distance from coplanar axis of rotation.

The buckling of a structural member induced by compressive stresses acting on a slender portion insufficiently rigid in lateral direction.

The tensile and compressive stresses resulting from the interaction of bending and shear stresses at a cross section of a beam.

The point in the cross-sectional plane of a structural member through which a transverse load must pass in order to prevent torsion or twisting of the member about a longitudinal axis.

Lines Depicting the direction but not the magnitude of the principal stresses in a beam

A graphic representation of the variation in magnitude of the external shears present in a structure for a given set of transverse loads and support

A graphic representation of the variation in magnitude of the bending moments present in a structure for a given set of transverse loads and support conditions

A beam or other rigid structural member extending beyond a fulcrum and supported by a balancing member or a downward force behind the fulcrum.

A net resultant of shear forces that acts vertically upward of the left part of the structure being considered.

A net resultant of shear forces that acts vertically downward of the left part of the structure being considered.

The part of the beam that is thickened or depend to develop greater moment resistance. The efficiency of a beam can be increased by shaping its length in response to the moment and shear values which typically vary along its longitudinal axis.

A simple beam supported by the cantilevers of two adjoining spans with pinned construction joints at points of zero moment.