Construction World March 2023

BUILDING

is not just for building management, but for the building’s tenants and visitors. The results are displayed on a public screen in the foyer of the building, to raise awareness and drive efficiency through user behaviour. Health and Safety Concor’s commitment to health and safety is non-negotiable, and the team was acknowledged by Anglo American for achieving 500 000 manhours LTI free. A full time safety team on site was responsible for Visible Felt Leadership and on-the ground education. This ensured adherence to safety and COVID protocols for all, including subcontractors. Concor’s Major Impact Prevention (MIP) meant all risks are identified for each activity, and appropriately addressed before the task begins. Quantifiable time, cost and quality An indicator of Concor’s fast pace of construction is that the four storey concrete structure was completed just eight months after bulk excavations for the three basement levels started. Larger foundation piles The decision to increase the size of the foundation piles allowed the columns to be cast over the piles. Traditionally, contractors would excavate around the pile and cast a concrete base or pile cap on top of the pile. However, by increasing the size of the pile, the need for concrete bases was eliminated. This resulted in a considerable time saving to the project. Once the piling subcontractor had cast the piles, Concor inserted the column starter bars into the concrete. Thereafter, the normal shuttering process was followed, and the concrete columns were cast. Decking could then be installed for the suspended concrete slab pour. Accelerating long lead trades Concor collaborated closely with the client from the start of the project to accelerate long lead trades. This facilitated a more integrated approach, with significant savings in time keeping the project on track. Premanufactured unitised façade Time was saved and quality ensured by using the same engineering firm for both the structure and the façade for the curtain wall. This allowed the design and manufacturing of the elements for the façade to begin while Concor was still busy constructing the concrete structure. Sophisticated software modelled the full façade around

reusing materials. At Ikusasa, Concor reduced the portion of ordinary Portland cement in its concrete mixes by 30% on average. The company also achieved 60% recycled content in its steel requirement. Low carbon concrete The project used concrete mix designs with a lower carbon concrete wherever possible, including all slabs. The low Portland cement content allowed the product to fit into the ‘green concrete’ category. Removing hazardous material A hazardous materials survey was conducted on site before the demolition of existing buildings, in accordance with the Occupational Health and Safety Act and other legislation. Any asbestos, lead or polychlorinated biphenyls found were responsibly removed in line with legal requirements. Training Four key members of Concor’s site team completed the Green Star (Interiors and New Built) online courses. This helped the team understand and apply sustainable ratings on the project, which contributed to achieving innovation points for the targeted Green Star Office and interiors rating Energy efficiency Ikusasa’s Green Star SA Net Zero Carbon Level 1 means the building generates as much energy on site as the base building requires. This includes the use of a photovoltaic solar generation system on the roof. Sub-metering enhances energy efficiency, by tracking and controlling the main areas of consumption. Any energy uses of 100 kVA or more are metered separately so users can benchmark usage targets and implement opportunities to reduce consumption. This reduces greenhouse gas and other emissions from grid electricity. Water conservation Ikusasa conserves water through low flow tap fittings, low flush urinals and dual flush toilets. There is also water sub-metering for uses such as irrigation and bathrooms. Plant irrigation was reduced by 50% using water-wise irrigation methods and smart sensors. Also, the heating, ventilation and cooling system is cooled by air rather than by water. Awareness and behaviour Data generated by the energy and water metering system is captured and analysed by a digital monitoring system. This

The Concor team for the Ikusasa project on the topped out structure.

30 CONSTRUCTION WORLD MARCH 2023