| PROJECTS |
The precursor to the trailblazing Square Kilometre Array (SKA) mid-frequency radio telescope project, the MeerKAT radio telescope is being further expanded with another 20 dishes. Concor was awarded the project to provide the civil engineering elements for the extension earlier this year and is now on site and busy with the construction of roads, dish foundations and other infrastructure.
Each dish foundation will have eight piles that are 7-11m deep.
An astronomical project C o n c or, t he l e a d i n g b l a c k- ow n e d construction company, in partnership with OptiPower, is building the foundations and infrastructure for 20 more dishes for the pioneering MeerKAT radio telescope. The SKA will be the world’s largest radio telescope and the MeerKAT project has already allowed astronomers to deliver unprecedented results. Its remote location in an arid area about 90km from the town of Carnarvon is ideal for its purpose, providing a “radio-controlled” backdrop for the mid-frequency array that enables the SKA’s work. According to Concor contracts manager Stephan Venter, the team commenced with the construction work on site in September 2021. Piling it on “With the piling rig on site, October saw our first piles drilled and concrete poured,” says Venter. “Soft soil and sandy conditions require that the 20 foundations are based on piles with a concrete cap. Each of these foundations has eight piles of 750mm diameter and 7-11m depth.” He highlights that precision is critical to the foundation construction, particularly the positioning of the bolt cage onto which each antenna pedestal is secured. These have to be accurate within fractions of a millimetre to avoid any deflection when the dish “looks” millions of light years into space. “In addition to the accuracy, the foundations must ensure that the antennae are able to resist the force of winds, especially as the dish has a wide surface area,” says Venter. “There’s also no room for any vibration of the dish.” The 1,7m-tall galvanised bolt cages – constructed to specifications locally – are carefully positioned on the blinding of the foundation cap before the rebar armature is
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PRECAST | ISSUE ONE | 2022
A mix of concrete
FOR THE MEERKAT EXTENSION PROJECT
assembled, the shuttering installed and the concrete poured. After the pour, the top of the bolt cage extends from the foundation for securing the dish pedestal or tower. Pre-tests and modifications Among the specif ic challenges of this project is the strict requirement to limit any radio frequency interference (RFI) in the vicinity of the MeerKAT telescope array. The highly sensitive radio telescopic equipment is designed to detect extremely weak radio signals from astrophysical sources and can easily be damaged by RFI from vehicle electronics, cellular phones and a wide range of other tools
