BENEFICIATION
Hollow-core slabs being installed at a housing project in Polokwane .
two truck-and-trailer configurations . With a combined weight of 44t , the hollow core slabs were placed in just more than four hours using a knuckle-boom crane that was easily positioned next to the structure . The scope of supply also included two flights of precast concrete stairs , which allowed for further time savings on the project . This approach also provided the building teams with a safer and more efficient means of accessing the second level .
Located outside the CBD , the factory is the heart of the operation , and this is where the company ’ s team also assists its clients , including architects and structural engineers , optimise the use of hollow-core slabs . A sound example is the use of the construction material to create stunning cantilevered balconies and outside entertainment areas , transcending the limitations of in situ construction techniques .
Hollow-core elements are manufactured according to SABS standards using cuttingedge technologies , including English Spiroll machines . The factory features specialised forms and moulds that guarantee accurate casting , a prerequisite for these projects . A separate steel-fixing yard also facilitates accuracy and therefore a high-quality reinforcing in the concrete casing .
Sensors constantly monitor the temperature and moisture content of the concrete mix and CoreSlab only sources its raw materials from long-standing supply partners . Only washed aggregates and sand enter the production cycle , and silica fume is used to create a denser micro-structure of the concrete .
Daily quality tests are undertaken at a fully equipped on site laboratory and test cubes are sent to independent laboratories for further inspection . To mitigate downtime , the company also has its own workshop and maintenance team .
New units for batching plant
In a recent development , CoreEngineering , CoreSlab ’ s engineering arm , commissioned equipment to enable the group to manufacture all the ‘ cast-in ’ components for its comprehensive range of precast concrete products .
The engineering division has played an instrumental role in Coreslab ’ s success as a source for all quality precast concrete items . This division is tasked with manufacturing all components for the Spiroll Extenders and other capital equipment used in the company ’ s batching plant .
The VM20i is a powerful CNC unit and is equipped with fourth Axis and Winmax9 software . With a spindle speed of 10 000 revs per minute ( rpm ), the VM20i is capable of accurately machining at 15.2m per minute with rapids of 24m .
De Bruin concludes that a slight increase in gross domestic product indicates that the country may have now entered a period of recovery , and this should have a positive impact on the residential property market .
“ This bodes well for an industry that has felt the pinch of under-spending by government on important social infrastructure compounded by the lack of business confidence in the private sector that has slammed the brakes on many large building projects ,” he adds . ■
28 _ QUARRY SA | MAY / JUNE 2018