Aurecon provided structural design, as well as construction supervision for the 24-storey Sonangol Head Office building in Luanda, Angola. The design overcame a number of structural challenges, including the height of the building and the addition of an extra floor to the post-tensioned floor system.
Aurecon utilised the very latest technology to ensure construction accuracy. Due to the height of the building, high strength concrete was specified for the columns and lift shaft for the first 12 floors, while the vertical accuracy of these lift shafts was monitored using laser beams.
In order to verify the foundation design being carried out by the Contractor, both the stiffness and the capacity of the piles needs to be determined. The method adopted for pile testing was the Osterberg Cell (O-cell) test method. This unusual method was adopted due to difficulties in obtaining appropriate equipment to carry out a more conventional pile test and to guarantee accurate test results.
Aurecon also performed quantity surveying for each floor by preparing a Bills of Quantities for the structural work and using an International Federation of Consulting Engineers (FIDIC) Condition of Contract to efficiently control costs and monthly payments.
The project saw Aurecon deliver a commercial office building taller than any existing structures in Luanda and included:
A basement below sea level to accommodate major services
A ground floor accommodating the main entrance and retail space