Tag Archives: Concor

WOLF WIND FARM PROJECT ADVANCES SWIFTLY WITH CONCOR

Work is progressing well on the Wolf Wind Farm in South Africa’s Eastern Cape province, with Concor carrying out the civils balance of plant – including an innovative design for a steeply inclined concrete road to the site.

The contract, which is being tackled in a consortium with Murray & Roberts company OptiPower for developer Red Rocket, will see Concor building 17 foundation bases for wind turbine generators on a ridge in the Klein Winterhoek mountain range. Concor Contracts Manager and Lead Project Manager for the consortium, Stephan Nel, explains that the bases are for two sizes of turbine: there will be five 6,2 MW Vestas V162 turbines – the largest in South Africa – and twelve 4,5 MW V163 models.

“The foundation bases for V162 turbines measure 22,5 m in diameter, while the V163 foundations are 21,2 m,” says Nel. “The larger bases will consume over 650 m3 of concrete each, with the slightly smaller bases taking almost 600 m3.”

Concor is conducting over 180 000 m3 of bulk earthworks for the base excavations and roadways on site – which includes 15 km of access road to reach the 17 wind turbines.  A total of 100 000 m3 of rock will be blasted during the construction of the project. After cleaning, a concrete lining is applied and specially designed anchor cages of steel reinforcing bar – weighing either 64 t or 70 t dependent on the base size – are installed.

Concrete from the batch plant at the foot of the ridge will – like all other wind turbine components and related equipment – have to traverse a steep 18% incline gradient to reach the top of the ridge where the turbines will be located. He highlights that this challenge required an innovative solution that could be rapidly executed.

“In collaboration with the client, consultants and specialist service providers, we designed a concrete roadway that could be constructed using the slipform method,” he says. “The 1,100 m roadway, measuring 7 m wide, was completed in January this year, paving the way for the on-schedule execution of the project.”

Among the challenges in the road construction was designing a concrete mix with a 35 slump – to prevent the poured concrete from moving on the slope – that would still be workable for the required window period. Nel notes that high daytime temperatures of 36 degrees C and above aggravated this issue further.

“After considerable planning, investigation and trialling, a solution was developed to allow the slipform paver and the cement trucks to operate on the steep incline, and to lay down the concrete road as planned,” says Nel. “The road was continuously poured at an advance rate of about 200 m a day, consuming some 1,600 m3 of concrete – reinforced with anchor beams and intermittent steel bars.”

KENDAL ASH DISPOSAL FACILITY NEARS COMPLETION

The Kendal Ash Disposal Facility expansion project, responsible for the storage of ash produced by Kendal Power Station until 2023, has successfully reached over 80% completion. With a projected completion date set for March 2024, this intricate venture is rapidly approaching its final stages.

Led by joint venture partners Concor and Lubocon Civils, the project accelerated its construction schedule over the winter, capitalising on the dry conditions. Concor’s Project Manager, Pierre Jansen van Vuuren, highlights the stellar productivity in June and July when the teams committed to continuous 24-hour shifts to gain momentum before the onset of the rainy season.

Spanning a massive area of 2.5 km by 3 km, the project’s components comprise the new 65 hectare Ash Disposal Facility (ADF), two dams each for both clean and polluted water storage, silt traps, an expansive 16 km V-drain system, a significant stream diversion and access road construction.

While the stream diversion and majority of the 14 km access roads have been completed, the principal focus now revolves around the ADF and the basins. 

The in-situ material is clay soils which calls for a specific construction methodology. Selected stockpiled excavated materials are being used in a double-layered low permeability clay for base protection, topped with carefully selected river sand to prevent liner damage. Cutting-edge drainage and leachate collection systems are incorporated to manage water flow efficiently, emphasising sustainability with dirty water reuse for dust suppression and other ADF activities.

Concor’s innovative approach in basin construction employs a patented PVC concrete formwork system, boosting efficiency by accelerating the casting panel process. This technique is not only time saving but also labour efficient.

Jansen van Vuuren accentuates the rigorous quality control measures in place. Leak prevention is paramount, with electronic leak detection ensuring construction integrity. “Our teams maintain open communication, emphasising the importance of the quality and structural integrity of the project,” he adds.

Challenges notwithstanding, the project is gearing up to finalise the liner system installation before the rainy season, with subcontractor Aquatan managing the basins and the ADF concurrently.

Highlighting the human element, Jansen van Vuuren praises the skilled workforce, noting that 852 locals have received training, and the project’s local procurement achievement stands at a remarkable 55%. 

He says this involvement extends beyond labour, and is aligned with Eskom and the Joint Venture’s CSI strategies, which are aimed at giving back to the local communities. By identifying local community recipients and working together with the contractors on its projects, Eskom ensures that the upliftment is extended beyond just employment opportunities. 

A good example associated with the Kendal Ash Dump Facility project was the adding of modular classrooms using containers and the fitting out of a kitchen at a local primary school, by the Joint Venture in conjunction with Eskom. This opportunity to give back addresses other needs within the community such as education and nutrition.

CONCOR IN COMPLEX HVAC INSTALLATION AT EASTGATE

To allow Eastgate Shopping Centre in Gauteng to upgrade its heating, ventilation and air conditioning (HVAC) facilities for greater energy and water efficiency, Concor is carefully strengthening the structure on which the heavy new chillers will rest. 

Concor Contract Manager Martin Muller explains that the HVAC system is located on top of a building on the centre’s roof parking area, in which tenants are active – and who need to continue trading during the renovation. Aside from the technical elements of the contract, therefore, clear and ongoing communication with the client and the tenants is a crucial aspect of success. 

“The construction work includes the demolition of an existing roof, walls and slab above tenants,” says Muller. “The structure will then be strengthened to ensure it can safely carry the seven 10 tonne HVAC chillers which are to be installed on the roof top building.” 

Due to the presence of a tenant running a call centre in the adjacent building, demolition can only take place outside of normal working hours. He highlights the importance of Concor’s safety culture in ensuring safe working practices at night.

What is important is for the considerable load of the new installation to be effectively transferred into the centre’s existing concrete columns under the roof parking – and hence down into the foundations. This is being done through the construction of interlinking stub columns which will create a grid to support the chillers. These columns are being cast systematically, working in a direction of priority for the HVAC specialists – so they can start their installations on the network of support steelwork and grating that Concor will provide.

The new structure will also include a transformer room, and a perimeter louvre closure around the HVAC area. At about 3,5 metres high, the louvre will improve the roof top aesthetics by concealing the installation from view. Concor’s team and subcontractors receive working-at-height training and work strictly according to safety protocols – especially since the HVAC rooms are 8,5 metres above ground on one side of the structure and 20 metres high on the other. Completing the project will be a steel roof, louvres to allow fresh air to cool the installation, access doors and a steel staircase. 

CONCOR CLINCHES CONSTRUCTION WORLD BEST PROJECTS AWARDS FOR TWO PROJECTS

Concor’ s name has long been associated with Construction World’s Best Projects with numerous of the company’s projects, both in infrastructure and the built environment, winning accolades over the past 22 years since the inception of this prestigious awards platform. This year has been no different with two of the three projects entered by the company securing podium finishes.

The large and challenging Trevenna Super Basement Project in Sunnyside, Pretoria – which has created a ‘future-proofed’ five level basement as a precursor for A-grade office buildings in the Trevenna Office Campus, received two Highly Commended Awards – one in the Building Contractors category and the other in the AfriSam Innovation Award for Sustainable Construction category. 

Covering almost 70,000 square metres of parking space and other amenities, the super basement extends 20 metres below ground level. This meant that the basement floor was 12 metres below the water table, creating significant groundwater and rainwater challenges. Hard rock conditions were also encountered and required controlled blasting and other excavation to reach the required levels. 

The Trevenna Super Basement is in a busy urban area, surrounded by high density residential accommodation. Community engagement was therefore key to the project’s success, as was careful planning, effective communication and a flexible approach from the contractors. 

Likewise the Eastgate Sustainability Project was also awarded two Highly Commended awards, one in the Building Contractors category and the other in the AfriSam Innovation Award for Sustainable Construction category. This project involves the extension of the solar energy generation plant, the installation of rainwater harvesting, storage and treatment facilities and the upgrading of the heating, cooling and ventilation (HVAC) system. 

Underpinning each of these fast track sub-projects is the demanding condition that trading activities at this busy shopping centre must be allowed to safely continue undisrupted. At a technical level, there are myriad challenges which the Concor team is successfully overcoming through careful planning, efficient execution and skilled workmanship. Demanding particular attention is the fact that most activity is being conducted on the centre’s roof parking level, where the load bearing capacity of the roof slab is a constraint.

Winning awards and securing podium finishes in prestigious competitions like Construction World’s Best Projects is a testament to Concor’s commitment to excellence and its ability to deliver outstanding results in both infrastructure and the built environment.

SHOPPING GOES ON AT EASTGATE WHILE CONCOR ADDS MORE SOLAR POWER

The addition of another 5,74 MW of solar power at Eastgate Shopping Centre, east of Johannesburg, is being undertaken by leading black-owned contractor Concor, while keeping the movement of tenants and shoppers unaffected. 

The solar panels to generate this power will cover 30,000 square metres of the centre’s roof top, according to Concor Contract Manager Martin Muller. This has meant careful planning of the sequencing of the project and management of traffic to minimise any disruption, says Muller. 

“We are conducting the project in stages so we limit work to one confined area at a time, leaving as much parking available to shoppers as possible,” he says. “We also meticulously manage the traffic flow to ensure convenience and safety.”

The location of the solar panels on the roof top has presented various challenges to the construction process. The low load bearing capacity of the roof top parking area, for instance, makes it off limits to cranes and readymix trucks. This requires Concor to use small dumpers for transporting concrete, and the company designed special scaffolding to accommodate conveyors carrying concrete into the column formwork.

The weight of the structural steelwork underpinning the large domes of solar panels is significant. This has meant that the concrete columns securing the steelwork have to be drilled and dowelled onto the existing columns supporting the roof top slabs, thereby transferring the weight to the centre’s foundations. This requires careful scanning and opening up of the column heads, to avoid any damage to the post-tensioned cables. 

Muller explains that the risk of the solar panel structure being lifted by high winds is also a factor that has to be considered during construction. This requires that the dowels have a pull-out strength of 12 tonnes – or 120 kN – each, and these are tested to ensure compliance with the specification.

“To speed up the project, we had the steel girders and trusses pre-manufactured and ready for installation,” he says. “The specific configuration of each dome was determined by the position of the concrete stub columns, so this demanded very accurate design parameters for the manufacture and installation of the steelwork.”

EASTGATE HARVESTS RAINWATER TO BOOST SUSTAINABILITY

Leading black-owned contractor Concor is constructing facilities to harvest and treat rainwater and groundwater at Eastgate Shopping Centre, adding to the centre’s sustainability and reducing its vulnerability to water outages. 

The new facility comprises two segmented steel tanks capable of storing about 200,000 litres of water. Rainwater runoff from the roof top parking area – which currently runs into the city’s stormwater drains – will be piped into these tanks. This will be supplemented by groundwater resources under the centre which will be pumped up and stored. These tanks are linked by a 300 metre water line to the centre’s existing buffer tank. Working in a live shopping centre environment, the water pipe has to be run through a busy parking area and across a public road, requiring careful planning and traffic management.

The tanks will hold over 200,000 litres, demanding a firm foundation. In preparation for this work, test pits were excavated to ascertain the presence of services, piping or ducting – as accurate as-built plans were not available. Concor considers these kinds of processes as vital to risk mitigation at every step of a project. In addition to uncovering various services, the test pits also revealed a concrete crane base some 500 mm in depth, which had to be removed before foundation works could begin.

In this case, geological conditions called for the use of twelve 130 mm micro-piles to ensure the stability of the tanks, following which raft foundations were cast over a 5 metre by 10 metre area. Construction of the foundations and the tanks is in close proximity to an existing LPG gas chamber that serves tenants such as restaurants in the centre. This requires special attention to health and safety procedures, including regulated permissions and certain restrictions on the use of electrical equipment in the area.

The project includes the installation of filtration and treatment facilities, ensuring that the water is potable for use throughout the centre. 

LOCALISED INFRASTRUCTURE UPLIFTMENT WITH LOCAL COMMUNITY PARTICIPATION

Local infrastructure development isn’t just about laying roads or erecting bridges; it’s about creating sustainable avenues for growth, development and integration. The localised upliftment of local road infrastructure connected to the Msikaba bridge Project is a shining example of how infrastructure can be a catalyst for community transformation.

Bridging Gaps – Literally and Figuratively

Laurence Savage, Project Director for the Concor Moto-Engil Joint Venture (CMEJV) – the main contractor – says the primary intention behind this project was to provide secondary access routes to and from the Msikaba Bridge for the CMEJV. While this was a pivotal logistical move for the construction phase, it bore more profound implications, he says.

“Firstly, these routes provide seamless access for the local communities, eliminating previous barriers and promoting integration. Secondly, they pave the way for potential economic upliftment. With enhanced connectivity, sectors like tourism now stand to gain immensely, opening the region to new possibilities,” Savage continues.

Scope and Span

The upliftment projects were divided between the North Bank and South Bank of the Msikaba Bridge Project, embracing a wide spectrum of road types. From the rehabilitation of surfaced roads on the R61 to re-graveling existing sandy terrains, the need for these improvements was apparent. But beyond the physical work, the incorporation of stormwater facilities in multiple areas denotes meticulous planning.

However, Savage says, the real triumph lies in the project’s socio-economic impact. “Over 40 local subcontractors were involved, illustrating an unwavering commitment to integrating local expertise and manpower.” 

A Commendable Effort by SANRAL

Notably The South African National Roads Agency Limited (SANRAL) deserves recognition according to Savage who says the involvement of SANRAL and the CMEJV brought a ray of hope to a place where economic activity has been bleak. “SANRAL has not just driven the development of roads but have also actively contributed to job creation in a region that desperately needs it,” he says. 

Key Achievements

The R61 stretch from Port St Johns, passing through Lusikisiki and Flagstaff to the Bazana turnoff, spanning nearly 100 km, has seen transformational change. From immediate pothole repairs to complete surface replacements in sections, the road has been revamped from a hazardous path to a user-friendly roadway.

Between Lusikisiki and the Msikaba Bridge, a combination of re-graveling and the innovative usage of geo-cell concrete roads has made travel safer and more reliable. Especially noteworthy are the taxi routes that were previously inaccessible in unfavourable weather conditions, which have now been made approachable.

Similar advancements can be observed on the Msikaba Bridge’s North bank, where re-graveling, geo-cell installations and stormwater systems have been integrated to better serve the rural communities.

Savage says that an environment-friendly approach was adopted with bush clearing activities, again involving local SMMEs, further pushing the agenda of job creation.

“It is significant that through these projects over 400 jobs have been generated, especially in the geo-cell projects domain. Furthermore, the CMEJV’s approach to training, mentoring and uplifting SMME’s is commendable,” he says. “This initiative not only imparts technical skills but also fosters a culture of quality, financial responsibility and adept project management.”

While the Msikaba Bridge Project and its ancillary developments are still a work in progress, what’s undeniable is the positive change it has heralded. The CMEJV’s pride in this endeavour is palpable and rightly so. Over the past two years, the region has seen more than just infrastructure development; it has witnessed the laying down of the foundation for a brighter, more connected future.

CONCOR CONQUERS ROCKY TERRAIN FORGING ACCESS FOR PHEZUKOMOYA WIND ENERGY FACILITY

Constructing wind energy facilities on mountains presents unique challenges, particularly in terms of accessing the construction sites. The Phezukomoya Wind Energy Facility, situated near Noupoort on the boundary of the Eastern Cape and Northern Cape provinces, faced such challenges during its start of its construction.

Concor, in partnership with Murray & Roberts OptiPower, forms part of the consortium responsible for the Phezukomoya Wind Energy Facility. The consortium was awarded contracts to construct the Koruson Main Transmission Station, as well as two of the three wind farms within the Koruson One development. EDF Renewables (South Africa) and its partners H1 Capital and Gibb Crede is developing Koruson One which was awarded in the Renewable Independent Power Producer Programme (REIPPP) Bid Window 5.

The primary challenge encountered by Concor, who is responsible for the civil balance of plant on this project, was establishing access routes to the mountaintops where the wind turbine foundations and hardstands are being constructed. 

Marritus Bezuidenhout, Project Manager at Concor, says establishing access was not straightforward as the rocky and difficult terrain required extensive blasting and clearing work before access routes could be constructed to reach the foundation positions.

To date, Concor has successfully delivered the civil balance of plant on more than 10 wind farms in the Western, Eastern, and Northern Cape regions, and Bezuidenhout says this experience played a significant role in optimising the construction activities on the Phezukomoya project facilitating preliminary access to some foundation positions while the construction of access roadways continues.

One notable aspect of the Phezukomoya Wind Energy project is the use of hollow foundations, a first for a wind farm in South Africa. Hollow foundations offer several advantages, including a reduced carbon footprint due to the use of less readymix concrete. The hollow design also allows for the inclusion of ducts and facilitates post-tensioning of cables for the tower, and installation of the power cables to the electrical reticulation network. 

“However,” Bezuidenhout says, “constructing hollow foundations is more labour intensive, requiring additional formwork as well as more steel reinforcing. It also requires precision work by the steel fixing teams to ensure the stringent tolerances are met.” 

Winter temperatures pose another challenge for the construction team. With temperatures often falling below 5°C, the casting of readymix concrete need to be carefully managed. To mitigate this issue, heat pumps are used at the batch plant while strict scheduling and control of concrete casting is implemented. Thermal blankets are also used during the curing process.

In addition to addressing construction challenges, Concor prioritised community engagement and skills development. A significant portion of the project’s staff comprises local community members who receive training and on-site experiential work. The company collaborates with local SMMEs (Small, Medium and Micro Enterprises), subcontracting services such as steel fixing, temporary ablution facilities, security, and transportation to the local taxi association.

EXCITING MILESTONE ACHIEVED BY CONCOR AT CONRADIE PARK DEVELOPMENT

Concor’s landmark R3 billion Conradie Park development has successfully completed over 800 homes, an exciting milestone in this ambitious project set to deliver approximately 4,000 homes upon completion. Mark Schonrock, Property Development Executive at Concor, says the achievement fuels the creation of a sustainable community within the development, a critical part of the Conradie Park vision.

The development, which began in January 2020, completed its first phase with the occupation of the Greenmarket complex comprising 432 units by January 2022. The following buildings, named after key Western Cape landmarks, Paarl Rock and Boulders, were occupied in September and December 2022, respectively. Construction of the next buildings, Silvermine and Kings Blockhouse, are currently underway and fast nearing completion.

The project has demonstrated innovation in building technology, incorporating city regulations such as constructing outside the 1-in-100-year flood line. This led to the creation of an engineered berm alongside Elsieskraal canal, blending functionality and aesthetics, creating a grandeur linear park for the Precinct. The buildings’ platforms were also raised to ensure safety against potential flooding.

Coming milestones for 2023 include the completion of the 91-unit Silvermine residential building, Kings Blockhouse, and four blocks of affordable rental accommodations. The largest node of the Conradie Park development, a mixed-use centre featuring 10,000 square meters of retail space, a 2,300 square metre gym complex, and 550 unit residential blocks is also on the horizon.

Upon completion of these upcoming developments, Conradie Park will house approximately 2,000 living units, marking the halfway point towards its goal of providing 4,000 new homes to the Cape Town community.

SPIRES SHOOT SKYWARD AS MSIKABA BRIDGE ADVANCES

The pylon spires of South Africa’s Msikaba Bridge mega project are on their way up, soon to tower almost 130 metres high at each side of the near 200m deep river gorge. 

For Laurence Savage, Concor’s Project Director on this contract, this momentous phase will reveal the sheer grace of the Msikaba Bridge design, and the awesome scale of the development. The Msikaba Bridge forms part of the South African National Roads Agency Limited’s (SANRAL) N2 Wild Coast project and is being constructed by the CME JV, a partnership between Concor and MECSA, both 100% black owned Grade 9CE South African construction companies.

With construction of the pylon spires underway at the Msikaba Bridge project, the scale of the development is quite apparent.
With construction of the pylon spires underway at the Msikaba Bridge project, the scale of the development is quite apparent.

Currently being slip-formed from the bifurcated legs of the pylons, each of the spires extend 95m from the bifurcation to the top of each pylon – taking the height of the bridge pylons to 128m. 

“The inverted Y-shape of the concrete pylons is strikingly elegant, and will become a hallmark of this iconic structure – as the design is architecturally elegant, diverging from the foundation legs, up towards the bifurcation and symmetrically converging to the top of the spire,” says Savage. “This is the largest cable-stayed bridge to be built in South Africa, and probably one of the most complex engineering bridge projects yet executed in Africa.” 

In this design, each pylon rests on two inclined legs which meet 21m from the start of the bifurcation which extends a full 11m. At 32m, the first section of the spire – starting with a diameter of six metres – is uninterrupted for 55,7m and comprises 14 slipform lifts. Then begins the inclusion of 17 anchor inserts over the next 35m of the spire, which reaches a height of 124m and will have converged to a four metre diameter. These anchor inserts accommodate the 17 cables that run from the anchor blocks located behind each pylon to the spire, and then down to the 580m long bridge deck. 

“To accomplish the lifts, we are using a jacking system for the formwork shutters, with eight jacks around the circumference of the spire,” he explains. “Each lift is 3,6m conducted at intervals of about two weeks per lift and we are making steady progress with quality and safety being paramount.”

The work is accessed using a specialised stair system, with one set of access stairs from ground level to the top of the bifurcation and a second stairwell to follow the shutter system up the spire. The formwork system comprises three decks that trail below each other; the interlinked decks lift together as the shutters are jacked up.

“The depth of the gorge – at around 197m – means that no work on the bridge deck itself can be done from ground level,” he continues. “Everything has to be done suspended from these two pylons – one on the south side of the gorge and one on the north side of the river.”

Like the leg of the bridge pylon, the reinforced concrete spire – with walls a metre thick – is hollow to reduce weight and is formed in a tubular design that significantly improves its strength-to-weight ratio. The reinforcing bar used in the spire includes 12 to 16 mm bar as lacing, with primary bars of 30 and 40mm bar employed in high densities to carry the significant loads. 

“Once the stays and bridge are in place, the load on each pylon will amount to around 7,000t,” he points out. The pylons are well advanced, with about half of the planned concrete volumes already poured by the top of bifurcation. After the last anchor insert, a four metre parapet will be constructed around the very top of the pylon spire. Access to the inside of the pylon will be restricted to engineering inspections and maintenance. 

“Indicative of the precision engineering being employed on this project is the number of activities that must take place at the same time – in a confined area,” Savage explains. “By the time we have completed the fifth anchor insert, for instance, we will have begun the launching of the first deck segment – followed shortly by the second and third segments. While these activities are taking place, the spire and inserts will continue to be erected and cast.”

Savage emphasises the intense focus on safety that has characterised the project, in line with Concor’s Zero Harm policy and protocols. Despite the high risk site which has included excavations of up to 17m for the pylon anchors, the site team recently achieved 3,5 million Lost Time Injury Free hours. Preparation for working at heights is a particular priority, with specialised training mandatory for these activities.

“This is all part of a training regime around safety, where we are continuously conducting risk assessments with our workforce,” he says. “The first item for discussion every day on site is the safety of their working environment; our primary value is care – both for yourself and for others.”

Savage highlights that when the bridge deck commences launching across the gorge later in the year, the culture of safety – inculcated in all workers over the previous years of the project – will be second nature to all. This philosophy applies across the approximately 300 people working on the north and south banks of the bridge, with some additional 280 people currently engaged in various community and local upliftment projects in the vicinity and a further 80 people in the engineering team and laboratory support staff.