Concrete Repair Posts

We offer the "how-to's" of Concrete Restoration

Posted by John Bors on Mon, Jun 25, 2012 @ 16:06 PM

epoxy stone restorationWe are an employee owned corporation formed in 1993. Our founders were six previous technical managers of Adhesive Engineering (AE), a pioneering company in the development of epoxies for use in both aerospace and civil engineering. When AE was sold and integrated into another company, ChemCo Systems was created to provide the highest performance polymer products and responsive technical service for applications in concrete repair, protection and restoration.

Use of two component structural epoxies in conjunction with automatic metering epoxy pumps to repair concrete started in 1959. At the request of Pacific Gas & Electric, two AE managers traveled in a station wagon to the Sierras to attempt repairs of cracked concrete in a hydroelectric dam. They brought some liquid epoxies and some pumping equipment and attempted to inject a mixture into spalled and cracked areas of the dam. They failed on their initial attempts to correct the problem but were invited back several months later and were successful in the repairs. The concrete was sampled by drilling cores and subsequent tests proved that it could be restored to its original monolithic strength with this innovative civil engineering repair. An extensive and costly demolition and reconstruction of portions of the dam was avoided.

Epoxy Solutions for Concrete Repair

We sell epoxies used for civil engineering infrastructure applications. More specifically, we focus on delivering solutions for concrete repair, protection and restoration to North American and international customers. Our customers include concrete repair specialists, general contractors, industrial manufacturers, utilities, state DOTs, airports and universities.

As a separate product line, we manufacture the world’s top performance paving, called Epoxy Asphalt (EA). Independent testing by universities in the US and Asia including Rutgers, the University of Texas, South China University in Guangzhou and Southeast University in Nanjing confirm that EA outperforms all other driving surfaces in fatigue performance which is a lifespan predictive factor for long span bridges which use lightweight (and flexible) orthotropic steel decks. In the last 10 years, EA has been placed on over 30 bridges in China and several other Asian countries including the longest oversea bridge in the world, the Qingdao Bay Bridge, and the longest main span cable stay bridge, the Sutong Bridge. We have local technical staff for Asia based in Tianjin, China; however, all of our products are manufactured in the U.S. and exported to Asia in sea containers.

Structural Concrete Repair Focus

There are several large companies that provide a broad range of construction related chemicals. ChemCo’s primary focus is repairing concrete used in structural applications. We serve this select niche through our approved applicator program, offering facility owners the assurance that this group of specialty contractors has undergone training at our headquarters and uses an integrated complete system of products and equipment from a single source (ChemCo). Instead of offering one or two of everything across all categories of products, we offer 6-10 choices of performance leading products in a select category such as epoxies for crack injection.

Third party engineers, architects and consultants will state that we are very patient in responding to unique repair challenges in all types of structures. Our reputation is based on our company culture which emphasizes our experience and integrity: most of our customers (many who have been with us for more than one generation of their ownership) know we will send them to the best alternate source if we can’t provide an in-house product solution. We’re happy to help with writing a repair specification, consult on the merits of alternate technical approaches or even create a test and custom product to fill a one-time need. 50% of our staff is an engineer or scientist. Rarely a customer who calls for information will be transferred more than one time.

Our reputation is partly based on producing the highest performance products in our specialized categories. We have not received a single return of product for quality or performance reasons since our facility moved to our current location in Redwood City in 1998. We emphasize safety in all departments and have not had a lost time accident since our founding in 1993. Our products are all 0 VOC and contain no solvents or toxics.

Repair epoxies for Re-purposing

A continuing trend of property owners is to make efficient use of existing facilities and waste less. Buildings and structures are more commonly recycled, reused, repurposed or rehabilitated than ever before. This trend is international; even China with its incredible growth, has created strong regulations which favor repurposing structures over the expedient option of demolition and starting over. Examples of building or facility repurposing where ChemCo has provided product solutions are:

  • Conversion of a multi-story warehouse to a data centerepoxy repair concrete column

  • Conversion of an old Folger coffee roasting plant to class A office space including seismic upgrades

  • Improving the foundation of a hospital to handle more load so additional stories could be added to the building

  • Conversion of a former Hubbell Electric motor manufacturing plant to a conference center seating 5500 for Living Free Ministry

  • Conversion of a paint manufacturing plant to a charter high school

Concrete Repair Case Histories

  • Holy Name Cathedral, Chicago A structural engineering survey found that many of the wooden timbers used to support the roof were marginal in load capacity. Steel dowels and our epoxy products were used to provide improved structural performance and fill checks and voids within the timbers. Some of voids had substantial volumes so a special low exotherm epoxy was used to avoid problems with overheated epoxy and shrinkage stresses.

  • Ochsner Hospital, New Orleans A custom epoxy was formulated to rebond concrete pile caps supporting the building that had large shrinkage faults caused in part by the exotherm of the concrete curing in bulk.

  • Fenway Park, Boston The dugout tunnels are partially located below the water table and players had to walk through puddles to get to the locker room. We provided an underwater rated epoxy injection resin and surface seal that cured at low temperatures so the work could proceed over the winter.

  • Stanford Green Library, CA Houses a rare book collection in basement. Concrete and tile floor on main level had excessive fine cracks which could potentially leak either during cleaning or if fire sprinklers went off on first floor. We provided ultra low viscosity epoxy healer/sealer to permanently penetrate and seal fine cracks with no discoloration.

  • Holcim Cement, CO One of the largest cement manufacturing plants in the US had challenges with concrete quality in their silo structure. We provided on-site training and high temperature resistant structural repair epoxies (extreme performance not offered by any other manufacturer) in this award winning repair.

  • SEPTA, Philadelphia This was a multiyear structural repair of elevated lightrail track and its supporting concrete. Special epoxy specifications were to withstand vibration during operation while the adhesive was curing. 

  • Denver International Airport Due to difficult geotechnical issues with underlying soils, runway slabs were subjected to undue movement and stress and required repair soon after construction. ChemCo injection resins surpassed the engineering requirements and restored the slabs to original monolithic strength. Pavement problems are a very critical item for airports as FOD (foreign object debris) can cause engine failure.

  • San Francisco Int’l Airport Similar challenge as DIA encountered except in terminal area slabs. We helped with construction specifications and supplied products to splice together slabs so they would not be displaced. No airport operations were affected and the terminal gates were available to the carriers each day.

  • Foxwoods Resort, CT One of the largest parking decks in the U.S., consisting of 500,000 square feet, had minor surface cracks and imperfections on the four decks (3 elevated). A yearlong product evaluation was conducted to identify a product which could heal the small cracks without altering the appearance and protect from spalling and future freeze/thaw damage and corrosion of the internal steel. ChemCo’s Epoxy Healer/Sealer was selected for the project which was performed over 2 summers so disruption of service could be minimized.

  • Chicago highrise The exterior cladding was composed of marble facing attached to precast concrete using steel pins. Over time, the panels were suffering from delamination and separation caused by water intrusion and freeze/thaw expansion. There was concern a panel skin could separate and cause damage on the sidewalk below. One of ChemCo’s experienced applicators worked with the building engineers to re-bond the panel skins using a ChemCo epoxy to the underlying concrete and eliminate any hollow gap between substrates.

  • Siemens LA Metro and other light rail systems  After a frustrating search for a system to apply over the metal floors of the electrical control stations of Siemens engineered light rail power control systems, we worked with one of our applicators in Houston to develop a non-conductive semi-flexible built up epoxy aggregate seamless floor with extreme durability.

  • Pacoima and Big Dalton dams LA area Subsequent to earthquake activity nearby these large reservoirs, engineering inspections determined that water leakage in enlarged cold joints could lead to weakening of the structure. So the reservoir levels were ordered to be lowered by more than 50% until repairs could be effected. ChemCo’s unique very long life epoxy with low exotherm was selected so it could travel long distances within the dam to help seal and repair joints.

  • Condo highrise A newly constructed condo highrise in San Jose was designed with a multilevel parking deck below grade. With a winter season rise in the water table after several years of drought, the two lower levels of deck were flooded prior to the opening of the building. Pumps were brought in to help lower the trapped water while an epoxy injection specialist patiently located nearly invisible cracks and areas of internal defects in the walls of the parking decks to inject them with a permanent underwater epoxy. Following a 3 week effort, the pumps were no longer needed and the walls were dry.

  • Colorado pipeline A concrete lined fresh water supply pipeline had been in active service for 40+ years. Its lining on the bottom was suffering from erosive damage by the sands that were transported as sediment. ChemCo was asked to provide a toughened, wear resistant mortar as well as a hard coating to ensure the integrity of the lining for years to come. All materials could contain no VOCs or flammable components.

  • Alamodome, San Antonio, TX An engineering inspection revealed that the original cementitious grout protecting the unique cable anchorages (the exterior cables are key architectural features) had shrunk exposing the connections to possible corrosion. A contractor was hired to restore the internal anchorages and requested that we formulate a low modulus polymer with no shrinkage and very long mixlife at high temperatures. ChemCo responded with a product (to replace a Euro material unavailable in the U.S.) in less than 2 weeks.

  • Dial Soap (part of Henkel Corp) New Jersey A manager who operates a 24/7 facility producing sanitizing products needed a highly chemical resistant coating to protect pipe trenches. He wanted to apply the system in very cold temperatures (below where most coatings can be used) and the substrate would be wet. We provided a two product combination utilizing a primer that can be applied under water and would cure very quickly despite nasty conditions. He called back saying he was surprised at the performance and ease of use and is now a repeat customer.

Gold Standard for Customer Service in Concrete Restoration

We are a responsive company focused on all aspects of customer service. About 85% of orders are shipped same day. We understand that many of our specialty contractors and their customers are under tremendous time pressure to perform a critical repair overnight, over the weekend or between shifts so our shipping department is adept at last minute deliveries—whether by truck, ocean, air or courier. No caller waits on hold very long and you will get straight yes or no answers from us. Our technical personnel have been with the company for 25 years on average so we generate conservative, experienced and field-tested advice. We don’t hesitate to direct a customer elsewhere if there is a better alternative product.

All of our Kemko certified applicators are required to have trained with us (at no charge) and offer their customers a complete single source system so there is no finger pointing between manufacturers in the event of a problem. We replace critical epoxy injection pumps of our applicators every 6 years to avoid aged failing equipment in the field. Our contractor customers remain with us for long periods—many are in their second or third generation of ownership.

With formulation, testing and engineering experience dating back to the late 1950’s, we have likely solved most challenging concrete restoration applications previously and can access these records quickly for reference. We encourage our customers to challenge us with unusual applications, extreme environments, difficult repairs and custom formulations. ChemCo product development, product testing and manufacturing is located under the same roof so information is shared quickly between departments. ChemCo owns and operates its own physical, chemical and environmental testing equipment and can simulate most extreme product applications without incurring the delays of outsourcing—our ability to formulate new products or evaluate difficult application conditions is not delayed by external testing.

Most of our competition sells primarily through distributors. We sell most of our product directly. As a result, we can offer the efficiency of direct shipping without an intermediary and related cost savings. If there is a critical need for technical support, our customer knows he can get it right the first time by calling us without having to work through channels. We won’t compromise on making product switches for convenience or merely because of excess stock of the wrong item.

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Tags: concrete restoration case histories