Engineering a legacy: Freedom Park Museum

The 52 hectare Freedom Park heritage site situated on Salvokop Hill in Tshwane overlooks the southern gateway to the city. Strategically located between the Voortrekker Monument and UNISA, it is a fitting location for the celebration of the rich cultural heritage of all South Africans and was one of eleven Legacy Projects launched in 2 000 by former president Thabo Mbeki.

The park aims to promote unity, peace and reconciliation amongst South Africans.

The Freedom Park Museum phase of the heritage site development is known by the name ‘//hapo’ (pronounced ‘Hlapo’) which is derived from a San expression meaning ‘a dream is only a dream if it is dreamt by the community’. Aurecon provided structural, civil, wet and façade engineering services for the 7 100 m² museum complex of buildings which houses interactive exhibits depicting the different epochs of South Africa’s history dating back 3,6 billion years.

The asymmetrically-shaped, interlinked buildings on different levels of the northern slope of Salvokop Hill are meant to represent a cluster of boulders which would typically form part of many African landscapes. The museum also houses an archive area, visitor centre and canteen.

The nature of the museum meant that many stakeholders were involved in its design, all with valid opinions and perspectives on the project. From a briefing point of view, this was especially challenging. Aurecon was closely involved in decision-making processes relating to the museum, which involved giving serious consideration to a multitude of views and perspectives and distilling them into a balanced, logical action plan.

The museum buildings are multileveled and designed to follow the natural mountain contours, taking visitors on a historical ‘journey’ as they amble through them. Creating an easily walkable, flowing route for visitors was therefore crucial. Engineering was pivotal in bringing this to life and required extensive interaction with the Office of Collaborative Architects (OCA) consortium responsible for the ‘look and feel’ of the building. Given the steep slopes of the site, Aurecon was called upon to design of a series of very technical, high retaining walls. The consortium later praised Aurecon for bringing their vision alive.

“The complicated geometries of the museum structures with their multifaceted facades were achieved in close cooperation with various role-players, including the architects and structural steel fabrication drawing detailers using 3D modelling expertise,” says Aurecon Project Manager, Tommé Katranas. “To express the architectural concept cost-effectively but as a durable landmark, structural steel was chosen as the only construction material that would accommodate these challenges.”

The primary construction system was a multilevel concrete frame supporting the exhibition floors with a top level of braced structural steel frames. A secondary steel frame system, consisting mostly of angle frames, enabled the ‘sculpting’ of the complex rock-like shapes the architects required, while providing the flexibility to make late changes and additions to the structure with relative ease. The use of structural steel supported by sophisticated 3D modelling also enabled the fast track contract to be completed in 24 months. The success of Aurecon’s design solution was reflected in the subsequent Southern African Institute of Steel Construction (SAISC) award for architectural steel.

After presenting various options for the façade engineering to the clients, copper cladding was selected in spite of it being a complicated, expensive material. Its advantages lay in its cultural symbolism and the beautiful patina it acquires which adds significantly to the intended rock-like appearance of the buildings. The engineering design challenge was linking a completely different from normal cladding medium to the complex geometry of the steel framework. The interface with glazing was especially complicated and needed careful attention to detail design.

The outcome was a unique façade for the museum that enhances the unique character of Freedom Park as a whole.

Since Freedom Park opened, it has become a place where both South African and international visitors find a haven to reflect on the past and inspiration for the future.

“The need to work closely together on the project with all stakeholders and listen to a broad spectrum of opinions from academics and political leaders, to spiritual leaders and the man on the street, was in itself symbolic of achieving the vision for a cohesive South Africa,” adds Katranas. “Last year, it was both rewarding and humbling to see that Freedom Park had achieved a special aura and was a focal-point for well-wishers praying for Nelson Mandela.”

Aurecon was originally appointed as part of a consortium to construct the services infrastructure for the Park as a whole (Phase 1), as well as the civil, electrical, mechanical, structural and wet services for this phase.

Aurecon, in joint venture with BEE partner Leslie Madinga Associates (LMA), was then awarded the tender for the design of all structural engineering services for the subsequent phases, including the monument (Phase 2) and museum (Phase 3).