Existing Types of Vaults:
Domes— A masonry dome produces thrusts down and outward. They are thought of in terms of two kinds of forces at right angles from one another.
Barrel Vaults— The vectors of pressure in this vault result in a downward force on the crown while the lower portions of the arches realize a lateral force pushing outwards. As a result, this form of design is subject to failure unless the sides are anchored or buttressed to very heavy building elements or substantial earthwork sidings.
Groin Vault— The construction of a groin vault can be understood most simply by visualizing two barrel vault sections at right angles merging to form a squarish unit. The resulting four ribs convey the stress loading to the four corners, or piers.
Thrust Network
Rib Vault— The intersection of two to three barrel vaults produces a rib vault or ribbed vault when they are edged with an armature of piped masonry.
Deflection
Funicular Form Finding
Deflection in spherical shells (diagram above): shallow dome is completely in compression and (lower diagram) lower portion of hemisphere dome tends to buckle upward and is resisted by hoop tension
Thrust reactions vary inversely with the depth of the arch
Load Distribution Arch are structurally very stable in compression, as loads are relatively evenly balanced through their form. Load distribution in the left diagram independent arches and a vault on the right The parts of a vault exert lateral thrust that requires a counter resistance. When vaults are built underground, the ground gives all the resistance required.
Parabola vs. Cantenary The catenary hangs under its own weight, while the parabola is carrying the weight of a horizontal deck below.
Parabola
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Fan Vault— The ribs of a fan vault a equal curvature and rotated at e distances around a vertical forming the conoid shape which rise to the name. In betw sequences of conoids, flat ce spandrels fill the space.
Cantenary