NMU Concrete Rehabilitation programme
Africoast Consulting Engineers was tasked by the Nelson Mandela University to Assess the present state of concrete corrosion (concrete durability survey) of the reinforced concrete structures and make recommendations and compile cost estimates for the required rehabilitation and maintenance.
The buildings and structures at the Nelson Mandela Metropolitan University – Southern Campus were identified to be in need of concrete rehabilitation works to the exposed concrete surfaces, waterproofing and maintenance.
The buildings and structures at the Nelson Mandela University are situated in a severe marine environment and are exposed to corrosive Chloride ions from the nearby coastal salt winds. The salt laden sea spray has over the years resulted in the concentration of the Chloride salts within the cover concrete, to the steel reinforcement.
The buildings and structures were experiencing a varying degree of corrosion related deterioration with visible degradation and concrete spalling which has led to the following primary concerns:
- Long term durability of the structures being at risk.
- Visible degradation of the structures.
- Hidden corrosion to the reinforcing steel that is not externally visible.
- Public Safety
Africoast Consulting Engineers managed to ensure that a total number of 27 “50 mm” diameter concrete core samples were extracted from selected structural elements from the above-mentioned structures using diamond-tipped concrete core drilling equipment.
The structures assessed and the test positions are as follows:
- Pedestrian Bridge
- Music Building
- Library Building
- Administration Building
The project budget in accordance with the rehabilitation strategies is R 7 870 149.42 inclusive of 10% Contingencies, 25% P & G, Professional Fees, disbursements and VAT, etc.