Looks like no one added any tags here yet for you.
Hanging cables structures work primarily in
Tension
A hanging cable structure is fundamentally unstable
In the sideways direction
The cable has a lack of rigidity to ensure
That the structure does not move excessively
A cable will change its profile
if the loads that are applied to it change location
Funicular structures
Structures that respond to a particular load situation by setting up pure axial forces within its elements (in tension or compression)
Polygon
Parabola
Catenary
Circular
Parabola
A funicular shape of a suspended cable loaded uniformly across its horizontal span
Catenary
A funicular shape for an unloaded cable and is determined by the self weight of the cable.
Single-curvature
Consists of two or more parallel catenary cables spanning between primary supports
Double-cable
Stabilizing cables below the primary suspension cables to resist wind uplift
Double-curvature
Anticlastic - suspension cables in one direction span between supports while the stabilizing cables run in a perpendicular direction and pull downward to prevent wind uplift
Lateral stability in the longitudinal direction is required, transverse guy cables
Single curvature
Have upper and lower sets of cables of different curvatures, pretensioned by tires or compression to make them more rigid and resistant to flutter
Double-cable structures
depth of the sag determines
The horizontal thrust that is generated
The less the sag
The greater the horizontal thrust
The greater the sag
The less the horizontal thrust
Membrane structures
Thin flexible surfaces that carry loads primarily through the development of tensile stresses
Tent structures are
Membrane structures prestressed by externally applied forces
To avoid extremely high tensile forces
A membrane structure should have relatively sharp curvatures in opposite directions
Net structures
Are membrane structures that have a surface of closely spaced cables instead of a fabric material
Cable net are
anticlastic
Shallow anticlastic tensile membranes must be
Pre-stressed
Cable net is a
Three-dimensional cable structure
when are the suspended and the arched directions of the membrane considered to share the load equally
Under gravity loading
pneumatic structures
Membrane structures that are placed in tension and stabilized by the pressure of compressed air
Domes are surfaces of
Revolution usually generated by rotating an arc of a circle around a vertical axis
A dome is similar to a rotated arch except that
circumferential forces are developed which are compressive near the crown and tensile in the lower portion.
Meridional forces are always
Compressive under full vertical loading
Hoop forces, restraining the out-of-plane movement of the meridional strips in the shell of a dome, are
compressive in the upper zone and tensile in the lower zone.
A tension ring encircles the base of a dome to
contain the outward components of the meridional forces.
Shell
A thin curved surface structure that transfers loads to supports by tension, compression and shear only
shells resist
tension
Synclastic surfaces
Doubly-curved and have similar curvature in each direction
Synclastic surfaces
Developable surfaces
Singly curved. Straight in one direction curved in the other and can be formed by bending a flat sheet.
Cones and cylinders or barrels are
Developable surfaces
Anticlastic surfaces
Doubly curved and have opposite curvature in each direction
Saddle shapes are
Anticlastic
Canoids are generated by
Sweeping one end of a straight line along a curved path and the other end along a straight line
Hyperbolic paraboloids are generated by
sweeping a convex parabola along a concave parabola of the same curvature
stresses in hypars relate to
the direction of curvature
Compression stresses
follow the convex curvature (Arch action)
Tension stresses follow
the concave curvature (Suspension action)
free form surfaces are
not mathematically derived
free form surfaces
Pure compression form
An arch
Abutment
Pier
Voussoirs
Keystone
Crown
Span
Rise
Haunch of an arch
Spandrel
Weak arches and usually used for inferior work only
Rubble arches
Rubble arch diagram
Ashlar arch
Monolithic Concrete Arch
Reinforced Concrete Arch
metal arch
Wooden arch
Rubble arches
They are made of rubble stones and can also be used as relieving arches
Wedge-shaped or tapered, joined with cement mortar and fully dressed
Ashlar arches
Stone arches
Ashlar and rubble arches
Concrete arches
Monolithic and precast
Suitable for larger spans
Monolithic concrete block arches
Precast concrete block arches
cast in molds
Tensegrity
a stable three-dimensional space where cables are continuous but struts are discontinuous and do not touch each other
An island of compression inside an ocean of tension
Tensegrity
A cable structure
Cannot bend
what needs supports at its ends that are fairly stiff
A hanging rope, Cable, or chain