The need for synthetic
macro fibers in concrete reinforcement came from customers, GCP Applied Technologies Director of Concrete Research Dr. Alex Reider said. Customers wanted the toughness of steel fibers, but without any of the disadvantages like corrosion.
- Faster and safer construction
- Lightweight reinforcement
- Superior crack control
- Enhanced durability
"The main weakness of concrete is its brittlenesss," Dr. Reider said. "It's very strong in compression, but once it cracks, you've lost everything. Concrete's like glass—very strong until the point of fracture. Then, you have two pieces."
Not so when STRUX® are added to the mix. After concrete cracks, the structure maintains because the
macro fibers bridge that crack.
STRUX® lightweight macro fibers, which are more durable and more efficient than steel alternatives, provide superior post-crack control. Even after a fracture, the concrete structure can still bear some load.
STRUX® macro synthetic fibers are a key component of the TYTRO® Shotcrete System.
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In this video, Ana White and her husband install Vycor® enV-S™ weather-resistive barrier on the exterior of their forever home in Alaska.
Contrary to traditional housewraps, the Vycor® requires no mechanical fasteners; it's self-adhered with a peel-away film for a flush bond with the wall substrate. Furthermore, Vycor® enV-S™ seals around fasteners during subsequent siding installation for an air-tight home.
Despite extreme weather and winds reaching upwards of 70 mph during the installation process, the Vycor® enV-S™ self-adhered, weather-resistive barrier withstood Mother Nature's test, remaining perfectly intact on the exterior of the White's house walls.
The Vycor® enV-S™ will also save the Whites up to $1,000 per year in home heating costs, even through the coldest, most bitter Alaskan winters.
Read more about the White's homebuilding project on Ana's blog…
GCP Applied Technologies has developed the
APPERTA® non-BPA coatings product line in response to market trends and consumers who see additional value in promoting the use of non-epoxy and/or non-PVC based formulations.
New advances in hi-tech analytical equipment allow detection of substances at extremely low concentrations.
In case a customer or brand owner is interested in preserving the non-BPA status of the coating, the guidelines below must be adhered to in order to avoid detection of critical substances that may lead to unexpected analytical results.
Potential areas of contact between non-BPA and residual BPA containing coatings may occur:
- At the coating application unit, due to poor cleaning of the coater. Critical points are tubes, hoses and pump.
- In a stirred container, due to an improperly cleaned stirrer.
- In the oven, by vapour-phase transfer of an external BPA-containing coating, if internal
APPERTA® non-BPA primer or internal system is applied first.
- In the oven, if the oven has been previously used to cure BPA-containing coatings.
- In the stacked sheet pile, assuming potential under-curing, if
APPERTA® non-BPA internal system is stacked in direct contact with the BPA-containing external coating. This is of specific concern if internal APPERTA® non-BPA coating is applied first.
The following recommendations will significantly reduce the potential for BPA cross-contamination:
- Properly clean all equipment before use.
- The stirrer must be completely free of any previous coating residue before use.
- The roller coater needs to be cleaned thoroughly, even those parts which are not in direct contact with coating.
- Tubes, hoses and pumps of the coater require special care and need to be rinsed with an appropriate thinner or cleaning solvent before and after use. Please refer to the section on thinner recommendations.
- If the oven has been used before with BPA-containing coatings it is recommended to clean the oven by running close to the maximum temperature (215 – 220 °C) for 45 – 60 minutes without feeding to attempt to purge the atmosphere of any residual traces of BPA.
GCP Applied Technologies produces and supplies DAREX® can sealants to customers all over the globe. DAREX® sealants ensure safety and quality in over 300 billion food and beverage cans each year.
In 1921, GCP developed “flowed-in” gasket technology, revolutionizing modern can production. More than 90 years and trillions of cans later, DAREX® sealants are still the foundation of the industry.
Broadest portfolio in the industry
Specially formulated DAREX® sealants have evolved in parallel with the industry, adapting to the ever-changing requirements.
This intimate, customer-focused customization allows GCP to offer the world's broadest and most technologically advanced portfolio of can sealants. The comprehensive DAREX® product portfolio includes products for beer and beverage, food, aerosol, composite, general line and specialty applications.
DAREX® is the only brand that offers both solvent base and water base can sealants. As the only global supplier of both technologies, DAREX® is attuned to the advantages and disadvantages of high solids, low VOC, HAP compliant solvent technology, compared to high solids water base technology.
With extensive experience applying both solvent-based and water-based can sealants at can makers around the world, GCP helps customers make the best choice for their operations.
Perm-A-Barrier® Liquid Flashing protects window and door rough openings from the damaging effects of air and water entry. It is fast and simple to use, providing numerous advantages to contractors and designers.
Air barrier benefits
The membrane protects against air passage and, thus, energy loss around window and doors. It minimizes air and water vapor flow through a building. The fluid-applied membrane is water vapor permeable, preventing moisture trapping in the wall cavity. It fully bonds to framing without priming and creates strong adhesion to common construction substrates such as wood, block, concrete, and metal.
Furthermore, the liquid flashing handily tolerates damp surfaces, eliminating the need for joint reinforcement tapes.
London's construction of the historic Crossrail line and its stations is the biggest infrastructure project in Europe.
Crossrail is one of the UK’s largest and most complex construction projects. Crossrail is expected to transform the rail network in London and the South East, reducing journey times and increasing rail capacity in central London by 10 percent.
Since work commenced in May 2009, 42 kilometers of new tunnels have been constructed beneath the streets of London, reaching depths of 30 metres. There will be 40 stations in total providing services for Crossrail passengers.
GCP Applied Technologies Waterproofing Solutions
GCP is the leading supplier of waterproofing on all major Crossrail Stations. To date, GCP has provided bespoke waterproofing solutions, detailing and site support to 8 major Crossrail stations – Bond Street, Tottenham Court Road, Farringdon, Liverpool Street, Whitechapel, Pudding Mill Lane, Canary Wharf and Custom House.
Tottenham Court Road
As part of the construction of the new £1 billion Tottenham Court Road Station, more than 2000 m2 of GCP’s
Preprufe® waterproofing membrane were chosen to deliver the high level of required watertightness.
Constructed by BBMV (a consortium of Balfour Beatty, Alpine BeMo Tunnelling, Morgan Sindall and Vinci Construction) for Transport for London, the new Crossrail station at Tottenham Court Road is the length of four football pitches and three storeys underground. With long term waterproofing performance, reliability and success at high-profile projects worldwide –
Preprufe® offered the perfect solution to ensure waterproof protection for this.
To complete the system solution, GCP also supplied
Bituthene® Liquid Membrane, AT System PVC waterstops, as well as
Adcor® hydro-expansive and injectable waterstops.
Over 5000 m2 of
Preprufe® waterproofing membrane has provided exceptional water tightness, below ground protection and proven performance at Liverpool Street station.
This new £300 million development, awarded to engineers Mott Macdonald/Arup and contractor Laing O’Rourke, is located below the existing Liverpool Street and Moorgate stations and Finsbury Circus. Two new ticket halls, Broadgate and Moorgate are being constructed, as well as a 40-metre deep shaft on Blomfield Street to accommodate ventilation, electrical, mechanical and systems equipment for the station. This area known as Bloomfield box, spans over a quarter mile in one of the busiest parts of London.
Preprufe® was the obvious choice for confined sites, for its reputation in providing a reliable waterproofing solution, preventing water ingress through and around the base slab. Its patented
Advanced Bond Technology™ enables concrete to aggressively adhere to
Preprufe®, forming a unique intimate seal which prevents any water migration between the waterproofing and the structure, substantially reducing the risk of leaks.
Utilising an advanced acrylic surface coating developed by GCP, the
Preprufe® membrane also simplifies the installation process by removing multiple layers and complicated detailing. Protective layers of concrete or boards are eliminated, reducing the depth of excavation and spoil, whilst the number of materials to be sourced are minimised, all accelerating the critical path of the project programme and ensuring the project was delivered on time.
Approximately 4,000 m2 of
Preprufe® 300R/160R, 1,500 m2 of
Preprufe® 800PA, and 250 m2 of
Silcor® liquid waterproofing were installed to provide exceptional waterproofing protection to the tunnel shafts, piled walls, base slabs and roof.
At the £500 million development of Canary Wharf Crossrail station, the 6,000 m2 application of
Preprufe® waterproofing membrane has ensured the site remains watertight – holding back up to 10 metres of surrounding Thames dock water.
Built in the West India North Dock by Canary Wharf Contractors Limited, construction of the new station has proven a complex engineering, technical and logistical challenge. Since construction began in May 2009, some 300,000 tonnes of material have been excavated, 375,000 tonnes of concrete poured and 1,000 piles driven to extract 100 million litres of dock water – the equivalent of forty Olympic-size swimming pools.
As part of the ‘top down’ construction programme, a four-level basement was completed to a depth of 28 metres. After draining the site and constructing a deep anchored cofferdam to provide a dry work environment, the next key step on the critical path was the waterproofing for the base slab. This needed to be installed quickly and effectively, in difficult conditions, to avoid delays to the following works.
In addition to its waterproofing performance,
Preprufe® was chosen for its ease of application and speed. The membrane is unrolled and loose laid, and can be applied even on wet substrates. The laps are self-adhesive and the whole installation can be achieved without welding or other special equipment. Once installed, no screed or other protective layers are required - the rebar installation and concreting can follow immediately.
Specified and installed at some of the most challenging waterproofing projects worldwide,
Preprufe® proved the perfect system for lead designer Arup and contractor Expanded Piling, a subsidiary of Laing O’Rourke. No other system on the market better protects a substructure from the harmful effects of water, vapour and gas than
For protection of the concrete joints and continuity with the piled walls, GCP also supplied a range of complementary products and systems including
Adcor® 500S and Adcor® 550MI, to provide hydro-expansive and injectable joint protection. The cold applied
Bituthene® Liquid Membrane and Servitite® AT240, a specially formulated PVC waterstop system, were also supplied to complete the project’s comprehensive waterproofing specification.
Other critical stations
As well as the above mentioned stations, GCP provided comprehensive waterproofing solutions for the other critical stations, including Bond Street, Farringdon, Whitechapel, Pudding Mill Lane and Custom House.
GCP offered bespoke waterproofing solutions providing continuity at the critical aspencts of the project. A full package was delivered consisting of Silcor® liquid waterproofing membranes, Adprufe® integrally waterproof concrete system and a full range of Adcor® hydrophilic and PVC waterstops available for concrete joint protection.
Designed to link with
Silcor® seamless waterproofing is a range of spray and hand applied liquid waterproof membranes, which provides highly durable waterproofing and structural protections without laps or complex detailing.
Adprufe® integrally waterproof concrete system, comprises of an innovative liquid admixture that significantly reduces both the permeability and drying shrinkage of concrete. It can be combined with GCP membranes and Hydroduct® cavity drain systems for enhanced protection in critical applications.
GCP’s hydrophilic waterstops unique ability to act as a continuously active seal due to its hydrophilic properties, means it works better than conventional waterstop systems, preventing water entry through joints in concrete sub-structures.
Set for completion in 2018, the Crossrail project - sealed in
Preprufe® pre-applied waterproofing membrane - will provide a vastly improved transport service which will benefit London, its inhabitants, and visitors for generations to come.
In this video, GCP scientist
Dr. Ezgi Yurdakul, Ph.D assesses the performance of
STRUX® 90/40 macro synthetic fibers in concrete, carrying load after cracking.
"(Fibers) don't necessarily prevent cracking," Dr. Yurdakul said. "Once cracking happens, however, the (STRUX® fibers) hold the system together to provide integrity."
This is crucial for the concrete to supply necessary resistance to load under cracking.
In the video, the concrete slab without
STRUX® cracks into pieces, under the bowling ball drop. When she applies the same test to a similar slab containing
STRUX® 90/40 macro synthetic fibers, no visible cracks form on the surface. Only minimal cracking appears underneath, but the integrity itself and overall shape of the concrete slab remain intact to carry desired load.
This basic experiment demonstrates how
STRUX® macro synthetic fibers provide enhanced durability and superior crack control.
Other benefits of
STRUX® fibers include faster and safer construction and lightweight reinforcement. These synthetic fibers are also non-corrosive, unlike welded wire or steel reinforcement alternatives.
CONTACT US ABOUT STRUX®
Ezgi Yurdakul is a concrete scientist in the R&D Division of GCP Applied Technologies, in Cambridge, MA. She received her Ph.D from Iowa State University, Ames, IA. She is currently the Vice Chair of ACI Committee 211, Proportioning Concrete Mixtures; Secretary of ACI Subcommittee 211-A, Proportioning-Editorial; and a member of ACI Committees 212, Chemical Admixtures; 325, Concrete Pavements; 506, Shotcreting; 544, Fiber-Reinforced Concrete; as well as ASA committees. Her research interests include shotcrete, mixture design optimization, chemical admixtures, and performance-based specifications for concrete.
At least 30 feet below the water table, the hydraulic forces compressed the worksite on all sides and made the walls immediately weep, when the extraction pumps, otherwise chugging around the clock, stopped working. So close to the Bay Area, the stresses at work were immense on waterproofing the gargantuan Transbay Transit Center in downtown San Francisco.
The problem: an asphalt-based fabric for below-grade waterproofing could not cure under the adverse jobsite conditions. The $4.185 billion project had plunged two and a half months behind schedule.
Luckily, project lead for the waterproofing contractor Dean Edwards knew what to do.
"We brought (GCP Applied Technologies) to the table," Edwards said. "We explained that
is a pre-applied, zero-cure waterproofing membrane. No wait and proven across hundreds of major infrastructure projects over the past 20+ years. What’s more, I believe in it. By taking curing off the table, we knew we could expedite the schedule."
Much like its aid in
sealing the Sacramento Kings' arena
in no time and keeping one of the largest infrastructure projects in the Middle East—the
Haramain High Speed Railway
—on track, GCP's
once again proved it is the "gold standard of the business," said Edwards.
With more than 500 million square feet installed across hundreds of high-profile public and private projects worldwide,
waterproofing membrane is designed to deliver…
- Fast, easy and straightforward installation
- A robust product design able to withstand wet weather
- Permanent adhesive bonding of the strong HDPE barrier to the concrete
- A clean, neat, asphalt- and clay-free product that is highly resistant to contaminated and aggressive soils
- Immediately trafficable with same-day rebar setting and tying
fully installed, the massive job is back on schedule and Edwards now has time to rest easy on the dry jobsite.
"We’ve been actually waiting on the general contractor to catch up with us."
Preprufe outperforms the competition
GCP Applied Technologies’ patented Advanced Bond Technology™ enables
Preprufe to adhere directly to dry or wet concrete and to form an intimate and impenetrable seal. Unlike mechanically attached bonding technologies which risk water migration between the mesh interface and concrete,
Preprufe is designed with synthetic adhesive layers and is combined with a robust HDPE film, providing a permanent physical barrier that protects structures against water and moisture, and chloride and sulphate attack even if their concentration changes over time.
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Preprufe is a durable and flexible waterproofing membrane that withstands harsh site conditions for a longer period of time than competitive waterproofing membranes. It can be walked on during installation without risking damage and is considerably faster and easier to install and detail than mechanically attached membranes. Protective layers of concrete or boards are eliminated, reducing the depth of excavation and spoil, whilst the number of additional materials required with mechanically attached technologies is minimized.
SF Transbay Transit Center builders applied GCP's Preprufe®
waterproofing membrane when nothing else would work.