Epoxerite, a leading South African producer of tailor-made chemical solutions, has invested in a new state-of-the-art testing laboratory at its factory in Westonaria, Gauteng.
Epoxerite, a leading South African producer of tailor-made chemical solutions, has invested in a new state-of-the-art testing laboratory at its factory in Westonaria, Gauteng.
George Weideman, managing member of Epoxerite, says that the new facility, equipped with the latest testing equipment, has significantly bolstered the company's already-high internal quality controls.
"We have earned a reputation for the consistent high performance of our solutions, which are being deployed in extremely demanding applications where there is no room for error. This development has reaffirmed our commitment to supplying products of the highest quality to our clients operating in the demanding civil infrastructure and mining industries," Weideman says.
The new facility has also been very well received by those contractors, suppliers and mining houses for which Epoxerite blends and packages grout products under their own labels. Regular testing ensures that these products consistently comply with exacting standards.
For example, the company blends and packages VSL Grout on behalf of VSL, one of the country's leading post-tensioning contractors.
VSL Grout protects the company's bonded PT strands against corrosion to ensure the durability of the PT tendons. This is in addition to serving as a bond between the tendon and the surrounding concrete.
Importantly, it needs to be predictive and consistent in all weather conditions.
Weideman and his team helped design the grout and participated in the testing of the new grout mix at an independent laboratory to ensure that it meets VSL Construction Solutions' very high performance standards.
The results of the testing revealed extremely good fluidity traits which, importantly, did not deteriorate significantly within 30 minutes from initial mixing. This provides an extended workability window for pumping without affecting compressive strength after 24 hours.
Fluidity testing was mainly undertaken according to T(0) and T(30), and the mix demonstrated sound workability of up to an hour when agitated constantly.
Moreover, the compressive strength far exceeded the acceptance criteria set by COLTO and EN447 within 24 hours in all related tests due to the high quality of VSL CEM1 cement that is used in the grout mix. This primary ingredient is sourced by Epoxerite from reputable suppliers and tested at its factory as part of the service.
A similar service is also being provided to M and J Mining, a manufacturer of a unique cable-grouting system that is being deployed in some of South Africa's deepest mines.
The grout needs to reach its compressive strength within four hours so as not to interrupt the blasting teams, while providing a long pot life to allow for the installation of up to 20 pre-stressed cable anchors in a single shift.
Moreover, it must be pumpable to fill the drill holes, which are between three metres (m) and 12 m in length and vary in diameter from 38 millimetres (mm) to 51 mm.
Epoxerite is also blending and packaging grout on behalf of CoreSlab, a designer and installer of prefabricated concrete structures.
Weideman also assisted the company in designing a special grout for its new precast-concrete reservoir-wall system that was recently launched in the country.
The grout reaches a compressive strength of 100 MPa within four days and will further react when the medium comes into contact with water when the reservoir is being filled to avoid leakage between the precast-concrete panels.
Importantly, the grout also has to be extremely flowable so that it can be pumped through all the post-tensioning ducts from a single position using two pumps. Its working time is extended by cooling it down to seven degrees Celsius.
Weideman says that the new testing laboratory also supports the imminent launch of a new grout solution that the company is developing for a leading civil-engineering contractor for the roll-out of information and communications infrastructure. This is in addition to other cutting-edge chemical solutions that are now in the testing phases and due to be launched imminently.
VSL Construction Solutions, a leading South African post-tensioning (PT) contractor, has introduced a new grout mix for its bonded PT systems used in building and civil structures.
VSL Construction Solutions, a leading South African post-tensioning (PT) contractor, has introduced a new grout mix for its bonded PT systems used in building and civil structures.
Paul Heymans, general manager of VSL Construction Solutions, says that the new grout mix is in line with the company's focus on constantly innovating to improve the performance of its PT technologies.
"Grout is a vital component of any bonded PT system. It serves a dual purpose in that it protects the PT strands against corrosion to ensure the durability of the PT tendons and also serves as a bond between the tendon and the surrounding concrete. The consistently high performance of the new grout mix will provide us with increased confidence we need on all our construction sites," Heymans says.
The new grout mix has already been approved by engineers and, as a result, been introduced on all of the company's projects.
PT Grout is blended by Epoxerite Products, a leading construction chemicals specialist, at its sophisticated plant in Westonaria, Gauteng.
George Weideman, managing member of Epoxerite, designed the new concept grout in association with VSL and also participated in the testing of the new grout mix to ensure it meets VSL Construction Solutions' very high performance standards.
Eight different grout mixes were tested at Contest Concrete Technology's laboratory in Durban, KwaZulu-Natal, to COLTO and EN445/447 standards.
Various grout mixes were first tested for fluidity and compressive strength.
Those that displayed the best flow results during flow cone testing and consistency based on visual assessments were then also tested for bleed and shrinkage using the Wick-induced test.
The Wick-induced test was undertaken to EN445/447 requirements, which is a more onerous test method than the COLTO specified test.
As the COLTO specification does not specify a shrinkage limit in grout, the EN standards were used as a guide as it establishes clear acceptance criteria for shrinkage at -1% and expansion at +5
Notably, the three samples were well within the limits set by COLTO and on the limit established by EN447 for bleed (0,3% versus 2% specified by COLTO and 0,3% specified by EN447) and shrinkage (0,6% average versus 1% specified by EN447).
The results of the testing revealed extremely good fluidity traits which, importantly, did not deteriorate significantly within 30 minutes from initial mixing. This provides an extended workability window for pumping without affecting compressive strength after 24 hours.
Although fluidity testing was mainly undertaken according to T(0) and T(30), the mix demonstrated sound workability of up to an hour when agitated constantly.
The compressive strength far exceeded the acceptance criteria set by COLTO and EN447 within 24 hours in all related tests. This is believed to be as a result of the high quality of VSL CEM1 grade 52,5N cement that is used as the primary ingredient in the grout mix.
VSL PT Grout is packaged in 25kg VSL pockets that are both safer and easier to handle by the company's skilled and experienced grouting teams on project sites.
Notably, the new grout also consists of Epoxerite's PT-Flow additive.
"We undertook numerous consultations with VSL and visited many of the company's sites. Importantly, the performance of the grout needed to be predictive and consistent in all weather conditions. Notably, Epoxerite PT Flow grout managed to also out perform all of the specifications, while being more cost effective than those used previously by VSL. Further savings were also recorded through declining stock shortages and reduced strain on equipment," Weideman says.
Heymans lauds the Epoxerite team for its stellar effort and willingness to assist VSL Construction Solutions develop and test the new grout mix.
"Epoxerite continues to provide a quality service to VSL Construction Solutions by undertaking regular testing of the materials and additives used in our grout mix. This has ensured a regular supply of high-quality grout and additives that we need to provide a cutting-edge service to our contracting clients," he says.
This leading construction chemicals specialist also supplies tailored solutions to other prominent participants in the civil, construction and mining industries.
"Products are tailored to the clients' requirements and specifications, and then packaged under private labels. VSL Construction Solutions is a demanding client considering the complex nature of its projects. The consistently high performance of its grout in these applications is testament to the high level of service that we provide our clients in the construction industry," Weideman concludes.
Post-tensioning (PT) concrete has become an integral discipline in the structural-engineering fraternity as is evidenced by the growth in the entire industry value chain.
Post-tensioning (PT) concrete has become an integral discipline in the structural-engineering fraternity as is evidenced by the growth in the entire industry value chain.
It grew from US$820-million in 2013 to US$860-million in 2016 in a trend that is expected to continue well into the future.
By 2021, for example, it is anticipated that the market value of the PT systems industry will have reached US$980-million.
Among the many global drivers behind this growth is Vorspann System Losinger (VSL) International with a track record that spans more than 60 years in the field.
Since 1954, the specialist contractor has registered more than 30 patents - the outcome of extensive research and development at its technical centres in Switzerland, Singapore and Barcelona.
The company's extensive experience in the field has also been harnessed by VSL Construction Solutions, one of South Africa's foremost building and civil-engineering contractors.
Paul Heymans, general manager of VSL South Africa, says that since its inception in 2002, the company has always maintained a strong working relationship with VSL International.
"Certainly, access to ongoing innovation and best international practice in the field has enabled us to retain our standing as one of the country's foremost design and construct PT specialists. This is on the back of our goal to maintain the highest possible quality standards and an ability to provide a cost-competitive service to the real-estate and state-driven infrastructure markets," Heymans says.
The company's comprehensive range of PT solutions, which includes both un-bonded and bonded PT systems, has been deployed on a range of technically complex projects across the country over many years.
The quality of grouting and the medium used in both its single strand and multi-strand bonded systems is critical on all of VSL's projects and is, therefore, undertaken in a carefully-monitored and controlled manner.
This is considering that the grouting acts as an effective protection against corrosion of the strands to ensure the durability of the PT tendons for any application, while also serving as an effective bond between the tendon and the surrounding concrete.
VSL Construction Solutions appointed Epoxerite, a leading South African chemical solutions provider, to source the CEMI 52.5N cement that is used as the primary grouting material from prominent local producers and package the product in 25kg VSL pockets.
Heymans says, just as importantly, the company is also tasked with ensuring a consistently high quality of supply that adheres to European standards.
"Certainly, we are also extremely appreciative of our service provider's willingness to test the cement regularly to ensure that the material meets our onerous quality requirements," he says.
"The selection of constituent materials, including both cement and additives, is one of the most important pillars for continuous and effective quality control. This is in addition to paying meticulous attention to the choice of the most appropriate mix design and adapting the mixing procedures to the selected materials, environment and equipment."
VSL Construction Solutions also places equal emphasis on the deployment of the correct equipment for mixing and pumping the flowable grout into the sleeves of the PT systems.
As a further quality control measure, these processes are only executed on site by qualified and trained personnel once the methods statements have been approved.
VSL Construction Solutions first approached the Epoxerite team to secure a regular high quality supply of CEM1 52,5N while working on the highly-acclaimed Mount Edgecombe Viaduct in KwaZulu-Natal.
Epoxerite packages the product under VSL Construction Solutions' label at its state-of-the-art factory in Westonaria, Gauteng, to ensure the correct grade and quality of cement is readily available while meeting safety requirements in terms of package size.
George Weideman, managing member of Epoxerite, says that he is proud of his long affiliation with a known leader in the PT field.
Notwithstanding a notable slow-down in construction activity in the country, Weideman points to ongoing developments in the PT field that bodes well for the industry value chain.
"These add to the overall body of knowledge available to deliver infrastructure and buildings faster and more cost-effectively. Certainly, VSL Construction Solutions' ongoing involvement in milestone projects, such as the Mount Edgecombe Interchange, as well as private property developments, such as The Pearls Of Umhlanga and 1 Whiteley Road in Melrose Arch, demonstrate exactly why the company has remained at the cutting edge of the African PT industry," Weideman concludes.
BKV Holdings devised a novel means of installing a Polyurea waterproofing over a Perlite cement fire-rated screed to wall system at a newly-built power station, and this approach has since become the standard on other similar projects.
BKV Holdings devised a novel means of installing a Polyurea waterproofing over a Perlite cement fire-rated screed to wall system at a newly-built power station, and this approach has since become the standard on other similar projects.
Perlite cement screeds are more porous than conventional cement aggregate types and, therefore, restrict the adhesion properties of Polyurea waterproofing systems.
The contractor also had to complete the application within seven days of laying the screed and was unable to wait for it to cure within the standard 28 day period.
A Polyurea waterproofing system is a hot-spray applied product with exothermic temperatures that exceed 100°C and the barrier had to, therefore, also withstand residual moisture in the Perlite cement outgassing.
BKV Holdings director, Brett Vermeulen, says that he approached Epoxerite to assist the company in developing a moisture barrier/faring coat that would be able to meet all of these requirements.
"The water-based, hydrophobic epoxy cement moisture barrier successfully adhered to the screed over which the waterproofing was applied, while also eliminating the exothermic outgassing phenomenon. An added benefit of the product that was only realised during the testing phases is that it sealed all surface blemishes and defects to provide a smooth monolithic finish. Certainly, our client was very pleased with the aesthetically-pleasing final Polyurea product," Vermeulen says.
The product achieves a compressive strength of seven megapascal (MPa) in seven days, 22 MPa in 21 days and 32 MPa in 28 days, while the solution has both a positive early height and hardened height change. Importantly, Du Plessis says that he is always looking for quality grouts at an affordable price, considering cost pressures in the beleaguered mining industry. "Grouting is a significant input cost. A reasonably priced product, therefore, also greatly assists us in being able to provide our premium service at an affordable price. This has been a key driver behind our success throughout the years," he says.
Pratley supplied the Pratliperl Perlite cement screed; NUI the Ultraprime 800EBA primer and Ultraspray the 402G12 Polyurea.
Epoxerite's E330 PEM underwent two months of stringent testing before being deployed on the project, and the leading construction chemicals specialist has since supplied about 6 000 litres of the product to the specialist contractor for several of its projects.
It is applied effortlessly over vast areas, some of which are up to 1 500m2 in size, using trowels and then floated to the desired finish.
Ease of use is another important trait of the product considering the nature of the bulk of the specialist contractor's projects, which are usually undertaken during short shut-down intervals in the petrochemicals, chemicals, construction and mining industries.
Epoxerite is able to provide its many customers with a full turnkey solution, which spans inspections, recommendations and drafting of method statements through to the timely delivery of products, as well as training in their efficient use. This capability complements the high quality of the company's products, the outcome of both ingenuity and integrity.
Weideman says that E330 PEM is a three-part cementitious-based epoxy mortar with high performance traits that make it very suited to the levelling and profiling of concrete, as well as other masonry substrates.
"It is an ideal moisture barrier on 'green' or very moist concrete, while also performing exceptionally well as a moisture barrier under polyurethane and epoxy systems or to seal pores in concrete. The PEM has also been used extensively in concrete repair works, serving as a smooth levelling layer over existing substrates of up to three millimetres in thickness," he says.
Some of the other key advantages of the grout include its rapid physical development traits; excellent adhesion to concrete surfaces; high moisture tolerance; and ability to cure under low temperatures.
It is also moisture tolerant, while providing extreme resistance to chemicals and facilitating the hydration of fresh concrete.
Weidemann concludes that he is proud of Epoxerite's long association with BKV Holdings and looks forward to working closely with the company on more of its future projects!
Epoxerite continues to build on its solid track record as a leading supplier of tailor-made chemical solutions for an array of applications in the mining industry and, among these, are the large volumes of high-quality grouts that it supplies for the decommissioning of tailings dams. These highly-regulated and complex projects rely on the skills and capabilities of only a small group of specialist contractors and their sub-contractors, such as Triponza Trading.
Epoxerite continues to build on its solid track record as a leading supplier of tailor-made chemical solutions for an array of applications in the mining industry and, among these, are the large volumes of high-quality grouts that it supplies for the decommissioning of tailings dams. These highly-regulated and complex projects rely on the skills and capabilities of only a small group of specialist contractors and their sub-contractors, such as Triponza Trading.
Triponza Trading is appointed to fill sections of drainage pipeline at the bottom of the ponds that run directly underneath the dam wall with grout. The exposed ends are then sealed to complete the stabilisation of the pipeline to avert a slope failure as part of the decommissioning process. The company has already sourced well over 200 tonnes (t) of C259PS from Epoxerite to fill pipelines with diameters of between 200 millimetres (mm) and 400 mm at prominent mining operations.
Phillip du Plessis, owner of Triponza Trading, says that he values the very high quality of the company's C259PS grout with its slight expansive nature, medium strength and thixotropic characteristics. "I am constantly investigating different grouting products to retain a competitive edge in this market. We need a grout that can be pumped easily over long distances, while also ensuring that there are no voids in the pipeline, and Epoxerite's C259PS offers such a solution," Du Plessis says.
Typically, the grout is pumped between 40 metres (m) to just under 200 m, and the use of a sub-standard medium that is not pumpable and flowable can result in substantial cost overruns for the contractor, as large rigs will then have to be deployed to drill down from the top of the tailing dam wall into the pipeline below to fill the remaining distances. Triponza Trading buys the C259PS in various bag sizes. They can range from 500 kg bulk bags to 10 kg polypropylene bags, depending on the terrain, accessibility, scope and size of the project.
The product achieves a compressive strength of seven megapascal (MPa) in seven days, 22 MPa in 21 days and 32 MPa in 28 days, while the solution has both a positive early height and hardened height change. Importantly, Du Plessis says that he is always looking for quality grouts at an affordable price, considering cost pressures in the beleaguered mining industry. "Grouting is a significant input cost. A reasonably priced product, therefore, also greatly assists us in being able to provide our premium service at an affordable price. This has been a key driver behind our success throughout the years," he says.
Triponza Trading has also retained its competitive edge by being willing to continuously test conventional limitations, including the existing traits of the grouts that it uses on its projects and, in so doing, the company demands robust technical support from its suppliers. Du Plessis deals directly with Epoxerite member, George Weideman, in researching and developing ways in which to constantly improve the qualities and performance of the product for these applications.
Epoxerite is able to provide its many customers with a full turnkey solution, which spans inspections, recommendations and drafting of method statements through to the timely delivery of products, as well as training in their efficient use. This capability complements the high quality of the company's products, the outcome of both ingenuity and integrity.
Epoxerite remains a leading supplier of high quality grouts for a myriad of applications in the mining industry, and this includes as a dependable bonding agent for pre-stressed cable anchors in some of the world's deepest underground mines.
Epoxerite remains a leading supplier of high quality grouts for a myriad of applications in the mining industry, and this includes as a dependable bonding agent for pre-stressed cable anchors in some of the world's deepest underground mines. This system provides a significantly safer alternative to the use of sticks to support stopes at the rock face, while also freeing up the necessary space for the introduction of mechanised technologies to significantly improve production.
M and J Mining remains a leader in the field, and is also the developer of the Flexibolt, a threaded pre-stressed cable anchor that is considered to be the future of underground primary support as mines continue to strive to reduce waste-rock haulage. It delivers an ultimate tensile strength of almost 80% of the cable - far exceeding that of any other product on the market.
Importantly, it also allows rock engineers to anchor higher into the hang wall of the stope than is possible using a conventional solid-steel roof bolt. Daniel Mathews, sales director of M and J Mining, says that the ability to innovate combined with robust internal quality-control systems have provided the company with a significant competitive edge over the years.
"We supply as much as 70% of the South African mining industry's pre-stressed cable-anchoring requirements, while up to 30% of our total output is now being exported to other prominent mining destinations on the continent, including Zimbabwe, Zambia, Namibia, Ghana, Mali, Ivory Coast and Tanzania, via our vast distribution network," Mathews says.
He adds that Dlamini Kuseni, who acquired a 26% stake in M and J Mining in 2012, has been a major driver of this growth, and he continues to steer the company into new markets. Kuseni also assists in the development of new offerings, such as the popular package deals that include high quality grouting mediums. They are produced and packaged under the M and J Mining brand at Epoxerite's state-of-the-art factory in Westonaria, Gauteng.
Epoxerite has been supplying all of the company's cable-grouting requirements for the past five years, and was appointed as an approved M and J Mining vendor based on its strong ethos. "We scrutinise the ethos of all of our supply-chain partners, considering our emphasis on quality control. Epoxerite has always been willing to discuss and understand our requirements, and this has led to a long-standing and mutually-beneficial partnership. I am certainly looking forward to building on this strong business relationship well into the future," Mathews says.
Extensive testing was undertaken on a number of mixes in underground environments to provide a grout that is suited to M and J Mining's unique applications. It reaches its compressive strength within four hours so as not to interrupt the blasting teams, while providing a long pot life to allow for the installation of up to 20 pre-stressed cable anchors in a single shift.
Moreover, it must be pumpable to fill the drill holes which are between three metres (m) and 12 m in length and vary in diameter from 38 millimetres (mm) to 51 mm. Regular batch testing is also critical to ensure a consistent high quality grout as is the accurate numbering of the 10 kilogram (kg) and 20 kg bags that are dispatched to the mines.
George Weideman, managing member of Epoxerite, says that the company is known for the high quality of its products and is, therefore, proud to be associated with a manufacturer that has a long legacy of servicing the mining industry. "Our premium solutions are the outcome of both ingenuity and integrity. They are especially suited to M and J Mining's applications where there is simply too much at stake for second-guessing, or second chances," Weideman says.
This partnership also demonstrates the critical part that participants in the supply-chain play in assisting mines innovate to raise safety levels, boost productivity and drive down costs in an extremely challenging economic climate. Weideman concludes that he is looking forward to working closely with the M and J Mining team in developing state-of-the-art solutions that will assist mines in boosting productivity and, importantly, creating safer environments for its many employees.
