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Elematic SA achieves SABS mark in fast and smooth audit

Elematic SA recently achieved accreditation from the South African Bureau of Standards (SABS), which entitles it to apply the SABS mark to all its products. Customers using any product which bears the SABS mark are assured of a consistent level of quality and reliability. In attaining this accreditation, Elematic SA (ESA) has provided its customers with further peace of mind via this assurance of quality.

Elematic hollow core concrete slabs are manufactured at ESA’s facility in Benoni, using state-of-the-art technology imported from Finland. ESA’s ability to rely on such technology, and on cutting edge research and development from Elematic in Finland, has always been beneficial to the business. In the case of achieving the SABS mark, ESA director Craig Webber points out that because all Elematic equipment is already designed to produce hollow core slabs that meet the EN European Standard, the process was made considerably easier.

When an organisation applies for accreditation, the SABS sends out an auditor to carry out an audit which essentially tests for conformity against a specified standard. This usually takes the form of some kind of quality management system. ESA began implementing the ISO 9001 quality management system some 18 months prior to the SABS audit, and all processes and procedures were therefore tested against this standard. The company contracted independent consultant Francois Beneke of Interlock Quality Consulting Network to assist in the implementation of the ISO 9001 system at the time.

Beneke, who is a concrete technologist, was able to assist ESA in ensuring that the ISO 9001 system was fully and correctly implemented. He explains that this is not always a quick or simple process, and that for most companies, it takes between 12 and 18 months to implement an ISO or similar quality management system. Most companies need auditing from scratch, and often systems and processes need redesigning and reorganising before they comply with the requirements of the chosen quality management system. “One has to produce evidence and keep a detailed paper trail in order to meet the requirements for the SABS mark,” Beneke comments.

He says that it requires a committed effort from management in any company to implement the system well, and comments that the close-knit team at ESA worked very well together. “We looked at everything right down to the computer software to ensure that the products comply with South African structural standards. We also tested everything against the EN and SABS norms,” he says. By the time the SABS audit was carried out, ESA’s systems had been tested thoroughly and the audit and accreditation process went far faster than expected. The audit involves an inspection of all the ISO 9001 documentation as well as physical tests on the product. All the different slab types manufactured by ESA were tested, and all were deemed eligible to bear the SABS mark.

Beneke points out that apart from the obvious benefit of attaining SABS approval, implementing a quality management system such as ISO 9001 has numerous spinoff benefits for any business. “In the manufacturing process, it is important to be able to get the quality of the products right the first time. ISO 9001 requires that companies carry out a self assessment on a regular basis, in line with the requirements of good corporate governance. If a mistake occurs, the system requires a detailed analysis that looks for the root cause of the problem, which means that one can’t just go for a quick-fix solution,” he says. All this adds up to a streamlined business which is ultimately more competitive and well run. Customer satisfaction surveys are also important, as they feed back into the self- assessment process.

Overall, the audit process at ESA went far faster than expected. “We went through a very quick assessment process. We didn’t need to implement any new procedures in order to attain approval,” says Webber. Beneke concurs, saying that the overall result at ESA has been excellent. “This is a good product and the audit was carried out in a comparatively short period of time. The team effort at ESA made a definite difference,” he comments.

Time and money saved on Protea Glen housing project

The use of Elematic prestressed hollow core concrete slabs on a housing project in Protea Glen, south of Johannesburg, has saved both time and money for the client. The project involves the construction of 176 sectional title housing units over two phases, and is being developed and built by RBA Developments. The first 108 units were built using traditional rib-and-block construction. The 68 units in Phase 2, however, have been built using Elematic 150mm hollow core slabs, which are manufactured and supplied in South Africa by Elematic SA (ESA).

Langdon Johnston, director at RBA Building Projects in charge of the project, says that at first, the company was reluctant to change from the tried and tested rib-and-block system. However, after discussing their needs with ESA director Craig Webber and a visit to ESA’s factory to see how the products are manufactured, RBA agreed to install Elematic slabs on Phase 2 of the Protea Glen project.

ESA is backed by Elematic in Finland, which was established in 1959 and is a well known and respected brand. Elematic Finland offers turnkey solutions for setting up production plants (it has done so in over 70 countries worldwide) and has ensured that ESA is equipped with state-of-the-art machinery and equipment. “When we saw the products in the factory environment, and observed that they are produced according to strict standards and with new technology, we felt comfortable to go ahead,” Johnston says.

After a visit to the site by ESA’s Occupational Health and Safety officer to liaise with RBA and ensure that the correct measures were in place, the Elematic slabs were delivered to site and installed in short order by ESA’s crane teams. “This system proved to be far faster and neater than the rib-and-block method,” comments Johnston. “We achieved substantial time and cost savings on the project, which is on a strict time line.” He adds that RBA worked with two different crane teams from ESA, and found both to be reliable and efficient.

There are several benefits to using the Elematic system. Because the manufacturing process is strictly controlled, clients are assured of a high quality concrete product. In addition, the slabs require no back-propping and no curing time on site. They are installed directly on site by ESA, and once in place, they require no plastering underneath. The joints between them simply need to be filled with silicone, and then paint can be applied directly to the soffit of the slab.

The Protea Glen project, which kicked off in June, is scheduled for completion in November, and is the first of a series of affordable rental homes which RBA is now developing. The company has previously developed stock in this category (ie R250 000 to R700 000 homes) for sale, but with tighter lending criteria imposed on consumers by the banks, the rental market is once again looking buoyant. Johnston explains that since the bank is happy with the model RBA presented to them, the company is now making efforts to develop other similar schemes – particularly in the affordable market. The idea is to create secure complexes with attractive landscaping and playgrounds.

Once this development is complete, RBA has another 153 unit complex coming onstream just up the road in Protea Glen. “We definitely want to use Elematic again on this new project,” Johnston says. “It was a pleasure to work with ESA and we are very happy with the product.” Both he and Webber note that the working relationship between the two companies on the Protea Glen project has been excellent, and both parties clearly intend to continue building a mutually beneficial business relationship. 

Elematic SA: The quality is guaranteed in the manufacturing

Elematic SA : Article for Civil Engineering magazine
Dave Soons

Although Elematic South Africa is only just entering its third year of business, this Benoni-based manufacturer of prestressed hollow core concrete slabs has already established an enviable reputation for quality – both of product and service delivery.

Product quality is guaranteed in the manufacture of the slabs, and it is easy to see why when one visits this 3200m² state-of-the-art factory, which has the capability of producing 40 000m² of high quality slabs per month using the latest machinery and technology obtained from internationally-acclaimed Elematic in Finland, from whom the company has taken its name.

Precast hollow core slabs are amongst the most technically advanced products in the precast concrete industry, and at Elematic it is a highly automated process utilising eight casting beds which, once they have been prepared and the longitudinal prestressing strands placed in position, the concrete is batch mixed, cast and kept in a controlled environment for 10 hours to attain strength before the slabs are cut, ready for delivery.

Computer controlled, the concrete mix is identical each time, although samples are regularly tested in Elematic’s own laboratory.   It is this attention to detail and striving for perfection which ensures that consistent product quality is guaranteed before the slabs get to site.

Elematic’s prestressed hollow core slabs are 1200mm wide, up to a 12 metre span are available in three standard thicknesses of 150mm, 200mm and 250mm - depending on the application – that can be used as floors, roofs and walls.

The longitudinal voids in the hollow core construction of the slabs can be used for technical installations such as ventilation conduits, plumbing and electrical pipework, but their greatest benefit is that they provide a 40-50% saving in concrete when compared with solid slabs, and the prestressing steel required is around 30% less.   Also, they need no transverse reinforcement.

Apart from the considerable time savings in availability and speed of installation, the hollow core slabs are much lighter and easier to handle and considerably reduce the weight of the floor, which makes them ideally suitable for any large span building such as offices, industrial premises, shopping centres and so forth.

The reduced weight of the slabs also provides savings in foundations and structural requirements in relation to solid slabs, and the longer spans require less support, which allows greater freedom in floor plan design.

These hollow core slabs can be used with all types of supporting structures such as bearing walls, skeletal concrete structures or steel frames, and they provide dry construction on site, with only the joints needing to be concreted.

Elematic has experienced teams available to erect the slabs on any contract and to emphasise the speed of installation, the system allows for between 500-1000m² per day to be completed on site.

The slabs are provided with a smooth, even bottom surface ready for decoration, thus removing the need for false ceilings.   The upper surface is etched to provide a key for floor screeds and similar following requirements.

Elematic slabs meet the requirements of the relevant sections of SANS Standard 1879-2004 Precast Concrete Suspended Slabs and SABS 0100/1 Structural use of concrete, whilst also conforming to the relevant EN Standards which in some cases are more stringent than the local standards.

One project currently nearing completion that is making full use of the speed of installation due to a very tight time schedule, is the 12 000m² Elematic hollow core slab construction at the new Registration Building for UNISA in Pretoria, which involves the provision of ground and first floor slabs for two administration blocks, a machinery room and a foyer.

Designed by structural engineering consultant HGK Consulting cc of Pretoria, this R130-million project is based around a structural steel frame. slabs.

Shear connectors were used to tie the slabs to the steel beams for structural stability.  Two steelwork suppliers/contractors were used on this project: JR Kopano Engineering cc and ProSpan Structures.

According to the structural engineers, this project illustrates the speed with which buildings can be constructed using a combination of structural steelwork and Elematic hollow core slabs, considering that the final design work was only started at the end of April 2008, and partial occupation will take place on 8th December.   “It was a challenging project in terms of timing, having to following such a very tight schedule, but the structural steel frame and hollow core slabs enabled this requirement to be met.”   Full completion of the project will be achieved early in the New Year.

The main contractor for this project is G. Liviero & Son Building (Pty) Ltd, which is currently enjoying its 25th year in business, and Contracts Manager Pierre Louw recommends the Elematic product and their site performance.

"With every supplier you need service delivery, and this is partially what made this project successful – the service delivery from Elematic has been extremely good,” he says.  "They did on average around 800m² each day, continuous, and this is much faster than conventional methods, particularly as you have no curing or prolonged soffit support to wait for and you can start work on the erected slabs the same day."

"For instance, in the foyer Elematic took two days to install the entire slabs, the next day we did the preparation, and that same night we poured the structural screed – so in period of just three days we had 1100m² of slab completed - much faster than conventional procedures,” he said.

"However, there is no doubt that to get the complete benefit of using these hollow core concrete slabs, Elematic should be included in the design team at the conceptual stage, along with the structural designer and the company providing the services."

Elematic had one other requirement to meet on this project, because rainwater is to be collected for grey water toilet flushing, and eighteen 10 000 litre water tanks were required – necessitating a standard 250mm slab being provided instead of the 200mm used elsewhere.   Special spacing of the tanks was also required to spread the load.

The industry is beginning to realise that Elematic's precast hollow core slabs are also ideally suitable for all types of residential installation and, because of their speed of erection these slabs have found favour with many developers.

Used for low cost housing as well, a contract was recently completed for a series of triple storey apartment blocks in Soweto, where the slabs were used to provide the first and second floors of the buildings.

Here Elematic slabs can play a very important role, helping to provide houses and other accommodation very quickly in a sector where this is of the utmost urgency.

Elematic slabs the right choice for Orlando Station Upgrade

The Orlando Station Upgrade project in Soweto is one of the critical links in the public transport chain, particularly in view of the forthcoming FIFA World Cup. Many soccer fans will make use of the station to visit the Orlando Soccer Stadium nearby during the tournament, and the station will continue to serve the need for public transport well after the event. The use of Elematic hollow core concrete slabs supplied by Elematic South Africa (ESA) on the project has helped save time and keeps the project on track for its planned completion time.

Construction on the R60 million contract began in August last year and completion is scheduled for April 2010. Gavin Munro – Contracts Manager for Motheo Construction Group, the main contractor – explains that a design and construct programme was decided on because of the unusual and tricky logistics on site and the minimal amount of time left to complete the project before the World Cup. The station handles some 20 000 passengers and 90 train sets daily, and had to continue to be operational during construction. When the contractor has required occupation certificates to work over the railway tracks for any reason, long lead times were required to arrange this and work often had to be done at odd hours in order to minimise disruption to the station traffic. In addition, there is a 3 000 Volt DC current running through the railway overhead lines, which makes work extremely hazardous.

The foundations and the main column structure still had to be cast in situ, while the main beams were cast on site alongside the railway line. The use of precast Elematic slabs, which form the floor slab in the station concourse, helped minimise the track occupation time required by the contractor when putting the structure together. The slabs are all cast off site at ESA’s state of the art facility on the East Rand. These were transported to site and, together with the main horizontal beams, were lifted into place during the course of two weekends using a 65 ton and a 400 ton mobile crane (the latter was required because of the large reach lengths).

"We have been very happy with the Elematic slabs and intend to use them on future projects,” comments Munro. "At the start of the project, we visited ESA’s factory on the East Rand and were impressed by the quality of the long beds in the factory, the consistent high quality finish of the underside of the beams, the fact that the products could be cut to any length we needed, and the fast turnaround time,” he adds. ESA uses equipment imported from Elematic in Finland to produce high quality hollow core precast concrete slabs in a variety of thicknesses and lengths. ESA also achieved ISO 9001 certification late last year, which adds to its credibility.

The station has been completely redesigned. The platform levels will now only serve to provide space for commuters entering and leaving trains, while all other station facilities will now be located on an approximately 2 000m2 raised concourse. New shelters will be provided at platform level for passengers, but all other buildings on this level have been eliminated, and the old subways have also been done away with. Commuters will enter the building at the level of the concourse, where they will book their tickets, and then descend to platform level to catch their trains.

An additional benefit offered by the Elematic slabs was that they weigh considerably less than a conventional concrete slab. Munro points out that the weight of the structure was an important consideration, especially given the size of the other structural components. The main structural beams are all 540mm wide and 1m deep and range in length from 2.8m to 14.7m. They range in weight from 1.8 tons to 23 tons. The shear columns are also extremely heavy and robust – the centre line in particular has to be able to withstand the impact of a train travelling at 60km/hour.

The  nature of the design and construct process means that there is always time pressure on a project, and on the Orlando Station Upgrade, the contractors were also working to extremely tight tolerances because of the way the structure was fabricated. A strict three-part quality assurance process has been applied at all times, and the project is on track for its scheduled completion date.

ESA director, Craig Webber, says the company is pleased to have been appointed on this project. “We believe we have established a good relationship with Nuway Motheo Construction Group Joint Venture and we look forward to doing more work with them in future,” he says.

ESA lands at King Shaka International Airport, KZN

Hollow core concrete slabs supplied by Elematic South Africa (ESA) are being used in the construction of four airline kitchen units at the King Shaka International Airport at La Mercy on the KwaZulu-Natal north coast. The units, which are some 500m2 each, are being developed by Whitehouse Projects (which will also be the landlord in this case) and will be used by large airline catering companies such as LSG, Airchefs, First Catering and Wings.

The new airport, which lies about 60km north of the old Durban International Airport and 40km from Durban central, is expected to be operational before the 2010 FIFA World Cup kicks off in June. Construction on the airline kitchen units started in January and is being completed in phases. Two of four units are complete at the time of writing, and balance are expected to be complete by June. The facilities are located on the airside of the main runway, and form fully self-contained units which are equipped for baking and cold storage. Each unit has its own upstairs office component. The entire complex also has its own water treatment plant.

Whitehouse Projects, which specialises in commercial refrigeration facilities, is constructing the project on a turnkey basis. Hubert Wahl, deputy chairman of Whitehouse Projects, explains that the construction process involves the initial erection of a structural steel frame with a Chromadek roof and cladding, followed by brickwork infill.  The specialised kitchen and cold storage facilities are then constructed by installing an insulated wall and ceiling system made up of a polystyrene core clad with a skin. Window and door openings are then cut into the wall panels.

Elematic slabs have been used for the structural slabs which form the first floor of each unit. These will accommodate the offices, together with small kitchens and storage space for administrative staff.  ESA, which manufactures the precast hollow core concrete slabs at its ISO 9001 certified facility on Gauteng’s East Rand, has transported the slabs overnight to La Mercy where they have then been installed by the company’s team on site.

The use of the Elematic slabs has had several advantages over conventional construction. The 150mm deep slabs span five metres in places. The precast slabs can be installed and grouted in just a few days, and there is no time required for curing.  “Because of the economies of scale, we are able to complete construction and hand over to the client much faster. The time saved translates into a cost saving,” Wahl says.

Whitehouse Projects first used Elematic slabs on a residential project, and the company was impressed with the quality of the product and the fast turnaround time. ESA director Craig Webber says that after this, Whitehouse insisted on using Elematic products, which now carry the SABS mark, for the airline kitchen units at King Shaka International Airport. “We are able to supply products to KZN quite readily and are pleased to have established such a productive working relationship with Whitehouse Projects,” he says.

Precast hollow core technology speeds up shopping centre construction

The use of Elematic prestressed hollow core concrete slabs has helped speed up construction on the Oakfields shopping centre in Benoni. The existing centre is undergoing a major extension which includes the construction of new premises for Pick ‘n Pay as well as the addition of several new line shops on a previously undeveloped portion of the site.

The new Pick ‘n Pay will be some 3 300m² in extent, while the line shops will take up an additional 1 300 m² around the anchor tenant’s position. Elematic hollow core slabs, which are manufactured and supplied in South Africa by Elematic SA (ESA), were used for the full 4 600m² of floor area in the new structures.

Simon Griffiths, director at L&S Consulting and the design engineer on the project, explains that the Elematic slabs have been laid on top of castellated steel beams on a 7.5 metre grid to form the roof of the new 500 bay parking basement below Pick ‘n Pay as well as the mezzanine flooring for the line shops. “Considerations we took into account when specifying the Elematic slabs included the fact that the product was cost-effective for our purposes. The price of building materials, including steel, has come down, so we could use the two in combination successfully.”

Griffiths adds that the main benefit of the product has been the speed with which construction can progress, because of the fact that the slabs are prefabricated off site. Construction commenced at the end of August, and the Pick ‘n Pay component is expected to be open by the end of February. “This system has definitely saved us time in comparison to a conventional concrete slab. The slabs also result in a lighter structure, which is beneficial where the weight of the structure is important,” says Griffiths.

Anver Arnolds of M&F Giuricich offers the contractor’s point of view, and concurs about the time saving benefits of using Elematic slabs. He comments that the installation has gone smoothly and quickly, saying that the speed of using this system has saved time on site. “We also found ESA very accommodating and we worked well together. We got all the information we needed easily and communication was excellent at all times,” he adds.

Griffiths also comments that ESA was very helpful in resolving any design queries with the engineers. Craig Webber, director at ESA, says that one of the challenges encountered was the fact that Pick ‘n Pay requires a high loading tolerance on the slab. Charles van Wyk, ESA’s design engineer, explains that Pick ‘n Pay requires a loading tolerance of 7.5kN/m² on the floor slab in the trading area, and 12kN/m² in the storage and despatch area as a matter of course. There were also longer than average spans to be covered.  The solution was to cast a 30MPa reinforced concrete structural screed 75mm thick on top of the 250mm Elematic slabs to create a floor which could withstand the specified loadings.

ESA manufactures its hollow core slabs using state of the art technology. It also has the R&D support of Elematic in Finland, which has a solid reputation based on five decades of experience. The benefits of using Elematic slabs include the fact that the prefabrication process under controlled conditions assures clients of consistent quality; the fact that the slabs can be installed quickly on site without the need for back-propping or curing time; and the fact that they typically require very little finishing once installed.

In conclusion, Griffiths notes: “We were already familiar with the generic system, but when ESA quoted on this job, we realised how cost effective it could be, and we have proposed its use on future projects.”