pin connection a joint in a
frame where the ends of the connected members are free to rotate
independently
pin support a support for a structure that restrains movement in the coordinate directions but does not restrain rotations
resistance capacity
of a member or component, or a cross-section of a member or
component of a structure. to withstand actions without mechanical
failure e.g. bending resistance, buckling resistance, tension
resistance’ (definition from EN 1990)
resultant a single force that is equivalent to a
set of forces: equal and opposite to the equilibrant.
resultant force action 1. see
resultant 2. an internal force action that
is mainly due to applied forces that are not close to the position
at which it is defined; for example, a bending moment is a resultant
force action because it is not caused by local forces;
roller support a support
that restrians only horizontal movement
rotation a vector that represents the angular movement
about an axis; normally measured in degrees or radians.
scalar a variable defined only by its magnitude
second moment of area property of an area
section the area revealed at a cut
shear force a force in a direction that is parallel to
the surface on which it is considered to act; internal force action
at a section of a member that acts parallel to the section.
shear strain the change, due to deformation, in the angle
between two lines on a body
shear stress shear force per unit area
spring force the force exerted by a body due to strain
energy.
statics the mechanics of bodies under the influence of
forces that do not cause them to move.
statical equivalence a force action or set of force
actions that balances a set of forces, equal and opposite to the
equilibrant
static equilibrium the condition that the vector sum of
the static forces on a body is zero
static force a force in a context where there is
no motion
statically determinate
a frame structure for which the release of one restraining force
action would convert it to a mechanism. i.e. to being unable to
support load
strain direct strain or shear strain
strength of materials models that predict the
resistance properties of a material as part of a structure.
stress force per unit area
structure ‘organised combination of connected parts
designed to cary loads and provide adequate rigidity’ (EN
1900)
structural analysis the use of structural mechanics to
predict the behaviour of structures under load.
structural mechanics the mathematical logic and
procedures used both for structural analysis and for technical
assessment.
technical assessment the use of design rules, that are mainly
based on structural mechanics and set out in code of practice
provisions, to assess the adequacy of structural members and
components.
tension the effect on a body of a force that tends to shorten
it
validation consideration of the potential of a process to
satisfy the requirements; consideration of whether a process has
satisfied the requirements.
vector a variable that has properties of magnitude, position
and direction and conforms to the rules of vector algebra.
vector algebra a set of rules for manipulating vectors
vector component a vector that together with other components
can represent a single vector, based on vector algebra.
vector sum the sum of a set of vectors.
web the vertical part of an I section
Young’s modulus the the ratio of direct stress to
direct strain in a material, assumed to be linear.