Qatar Academy Al-Khor

Project summary provided by submitting company.

There were a total number of 9 buildings, with 2 floors and a total area of 595,155 sq. ft. The exterior perimeter was all tilt-up insulated reinforced concrete panels, with some interior reinforced concrete shear wall solid panels. Inside, there are precast columns, precast and prestressed beams and hollow-core slabs. Reinforced concrete screed was then cast on the hollow-cores and joined with the tilt-up panels to form the rigid diaphragm of the structure. The spans of the concrete beams were around 7.2 meters. In one of the buildings, there was a gym inside where it's roof was supported by prestressed reinforced concrete I-beam Girders spanning 21.5 meters, supported on precast columns. The external Tilt-Up walls were extended about 2.6m above the Finished Roof Level acting as a parapet to conceal the mechanical and HVAC equipment on the roof.

1. Precast columns = 583 pc.
2. Precast and prestressed beams = 953 pc
3. Hollow core slabs = 5945 pc
4. Precast stairs= 81 pc
5. Precast landings and slabs= 90 pc

This project was the first Tilt-up project in Qatar. It was re-designed from conventional concrete construction to tilt-up, after the tilt-up contractor/specialist convinced the general contractor and the Client that the tilt-up system will reduce cost and expedite the construction process, where the tilt-up contractor also carried out the redesign of the project. This value engineering in switching to tilt-up resulted in achieving around 15% cost savings (of the skeleton works' budget) for the General Contractor (GC) and the client; thus securing the contract for the GC.

The inherent characteristics of the tilt-up system of being able to build relatively wide, tall and heavy wall panels cast on site, made it possible to meet the project's tight re-design and construction schedule in terms of time, quality and cost (post value engineering). Furthermore, its inherent fire resistance, sound and heat insulation and the durability of concrete as a structural material has met the satisfaction of the project owner and end user, and gained their confidence in the system to last for many maintenance-free years to come.

The insulated tilt-up concrete wall panels made it possible to meet the project's required U-Value, with a total concrete thickness of 300 mm (150 concrete/50 insulation/100 concrete), utilizing top of the line composite connectors by Thermomass, compared with the original conventional block work system of 500 mm. During the re-design and build phase, the specialty Engineer working with the project design team, have managed to capitalize on the strong features and characteristics of the tilt-up system to adapt it successfully to the footprint of this relatively large project with almost repeated foot prints for each of the 9 buildings.

All foundations and skeleton works (using tilt-up) of the 595,155 sq. ft. of the project buildings were completed in 6 months, the entire completion of the project took 12 months. Due to the fast speed of construction using tilt-up, finishing works inside the buildings started only after 1-month of construction.

Notes:

• The project contained one of the tallest and heaviest panels in the region
• Adaptability of the tilt-up system to the projects requirements and footprint, as the project was initially planned as conventional, and speed of panels production and erection in 6 months
• The labor force was unskilled (first time for tilt-up), and yet the tilt-up contractor managed to train the labor and finished the project in an extremely fast time-period.
• The needed quantity of timber form-work was reduced by almost 90%, due to the tilt-up system of construction.
• Because of using tilt-up, there are less workers' safety hazards from working at heights and falling, since most of the work is done on the ground slab. The project received a safety award of: One Million Safe Man Hours
• The project was completed 1 year ahead of the initial schedule, and was completed in June just before the commencement of the new school year for the students, so it had a significant impact on the community at Al Khor/ State of Qatar.
• Due to the use and implementation of the tilt-up system, the number of workers was reduced by almost 50% than needed in conventional construction, so less workers are exposed to health and safety hazards
• Due to using tilt-up as the construction method, the Contractor and Client saved about 15% of the skeleton works budget.
• Major reduction in construction material Waste.
• Major reduction in Transportation activities related to the construction process (Less CO2 emissions as a result).
• Major reduction in future maintenance as a result of using Tilt Up Vs. Conventional construction.
• Energy Saving as a result of delivering Insulated Panels.