Design of the new Ghazy al Gossaibi Mosque

General information:

Project Name: Design of the new Ghazy al Gossaibi Mosque

Date (year): 2022

Client: MYAA Architects & PGI Engineering & Consulting

Location: Al Jubail, Saudi Arabia

Property photo: PGI Engineering

Project summary:

The Ghazy al Gossaibi Masjid project is located in Mardumah Bay in the city of Jubail, Saudi Arabia. The concept design defines a seashell-shaped roof and represents a new iconic building on the ledge of the bay in Jubail.

Structural engineering concepts have been created in conjunction with the architect and building services and civil engineers. Solutions have been devised that meet the architectural and engineering requirements.

Project details:

• Structural Challenge

The proposed structure consists of longitudinal main arches with different curves. The structural behavior of the arches will be that of a frame since the curve has no relation to the funicular loads.

Due to the design of the exterior and interior geometry, some of the frames have two overlapping arches that create the roof and its overhung on the front facade accommodating the roof openings. The horizontal reactions at the base of the frames are important and are considered a rigid base and foundation.

Structural stability of the mosque is provided by steel frames in two orthogonal directions.

In addition, a concrete core on the left side of the building and some steel suspenders are also used for horizontal stability against wind, seismic and concentrated loads.

Due to the complex design of the steel structure, the profiles have been previously welded in the workshop and assembled to the rest of the structure on site by means of bolted connections.

• Keys to the structure

A steel structure allows an easy and fast assembly achieving the shape and geometry of each arch.

There is no need for a material execution control to check the real resistance acquired by the steel. The material itself guarantees the designed resistance.

A lightweight structure means less impact on the foundations.

Most of the structure can be fabricated in large pieces in the workshop, and only the assembly between the parts will be done on site.

The infill material between arches will also be a metal deck slab with a top layer of 8 cm cast-in-place with minimal reinforcement. No formwork is required for this metal deck slab platform, as it is supported on arch-to-arch beams.

• Decisive elements

In order to minimize obstacles to the construction of the steel structure, Socotec Spain devised a strategy to extend the protection time: improving the structure's resistance to atmospheric corrosion by oversizing the steel elements.

The structure is thermally protected (i.e. it is not exposed to large temperature changes) because it is also finished with sprayed Vermiculite as fire protection (it also makes a thermal cushion). On the other hand, Iterchart's supplier ensured that with an adequate paint thickness, 15-20 years of environmental protection could be achieved.