Jack Arch Roof Construction Details

A jack arch is a structural element in masonry construction that provides support at openings in the masonry.

Jack arch roof construction details.

A jack arches constructed with bricks laid on edge in a single course with lime mortar or cement mortar of specified mix and supported over steel or concrete i shaped joists and having a suitable ceiling finish applied on to its soffit. Jack arch roof construction where trapezoidal reinforced concrete beams are used at intervals between which hollow terra cotta blocks form small elongated multiple vaults. Instead they are flat in profile and are used under the same circumstances as lintels. The joists are spaced 1 0 to 1 5 m centre to centre and are supported at their ends either on walls or on longitudinal girders.

Jack arch roof is composed of arches of either brick or lime concrete supported on lower flange of r s j s. Alternate names are flat arch and straight arch. The rise of the arch is kept 1 12th of the span. Above them concrete fill is laid providing a level surface upon which the flooring finish can be if there is another level in the structure.

Design considerations 5 1 general 5 1 1 the jack arch built up floor or roof shall consist of the following components. The more traditional ones are called jack arches where the arches are formed in the roof itself supported by the centering while the recent researched type is arch panel roof where the arches are made on ground to be lifted up and placed.