Brick Jack Arch Flooring

These floors are formed through constructing brick or concrete arches called jack arches on the lower flanges of mild steel joists.

Brick jack arch flooring.

Brick jack arch flooring. Brick masonry arches have been used for hundreds of years. Figure 1 illustrates jack and segmental arches. The victorian jack arch floors had larger brick arches around 1 5 m wide with a maximum rise of 20 cm.

Alternate names are flat arch and straight arch. The masonry arch is one of the oldest structural elements. Only first class bricks should be used. Major arches are those with spans in excess of 6 ft or rise to span ratios greater than 0 15.

Successive rings should be properly interlocked. In this issue of technical notes an. The later 20th century floors however were constructed using smaller brick arches 80 cm 1 0 m wide with an average rise of 5 cm so that a flat surface could also be created for the ceiling by direct plastering. It was not a flat arch in the us sense of the term rather the jack arch consisted of shallow brick or concrete vaults spanning between iron or steel joists.

The floor slabs constructed using the steel i beam jack arch system are stable under normal static conditions as the brick arches transfer the gravity loads mainly in compression along the arch. Used throughout the 19th century for its incombustibility and strength the jack arch was a widespread form of floor construction. After that centering board is cut slightly at the ends and is made to rest on the lower flange of rsj along with the curved surface upwards. Many of the different types of brick masonry arches are discussed and a glossary of arch terms is provided.

Brick jack arch flooring. Key brick should be properly and tightly secured in rich mortar. The equilibrium polygon lies completely within the middle of the arch. The construction on jack needs centering of 30 to 40 mm thick segmental piece of timber along with chord length equivalent to the span of the arch and conforming to the soffit.

Before starting the work the rsj should be properly secured in position. The reaction passes through the lower 1 a point of the arch at the skewback. Unlike regular arches jack arches are not semicircular in form. This technical notes is an introduction to brick masonry arches.