FRP Anchors



The most common FRP strengthening involves carbon or glass FRP sheets that are adhered to the exterior surface of existing concrete, masonry or steel structures. When the existing substrate is either concrete or masonry, the surface mounted FRP behavior is almost always controlled by debonding from the substrate. This undesirable failure mode leads to under-utilization of the high tensile strength of FRP. Specially designed and detailed FRP anchors can tie this surface mounted FRP deeper into the substrate and allow much more of the FRP strength to be used. This means less FRP to achieve the same level of strengthening. For seismic applications, anchors can help delay debonding and allow the structural element to behave in a more ductile manner. National design guides, such as ACI 440.2R (published by the American Concrete Institute) recognize the beneficial effects of anchorage on the strength and deformability of members strengthened with FRP.

Typical FRP anchors are shipped to the site as loose bundles of fibers. Although effective, such anchors can be difficult to saturate and install and do not provide the high level of standardization, product quality control and field quality assurance that rehabilitation projects require and deserve.
Külstoff believes that designers and installers of FRP should not be subject to such limitations as they strive to deliver high quality work.

With this in mind, Külstoff developed and patented a precured anchor that provides superior performance, is factory-fabricated for complete product standardization and offers extremely high field production rates, while maintaining excellent installation quality assurance. This anchor has been thoroughly tested by Külstoff, as well as by researchers worldwide.

Külstoff also manufactures a through anchor, or connector, to allow load path continuity for FRP interrupted by structural members, such as vertically oriented FRP on a column between two floors. The through anchor allows the columns FRP to be "continued" through the floor slab or beams.

In keeping with your commitment to promote high levels of QA/QC, we have also developed an innovative anchor saturation tray. When used with our anchors, it provides the installers with assurance that they will achieve complete saturation of the anchor fibers with the saturating resin or epoxy.

See below to learn more about our anchors and to see how easy they are to work with...



Külstoff Embedded (or Spike) Anchor



Külstoff's patented embedded anchors (BA-PCA) are factory-fabricated for full product quality control. The anchors are made from the same materials as the FRP being used on the project. In addition, a specialized epoxy coating is used to adhere aggregate to the precured portion of the anchor. The anchor design and installation methodology is intended to eliminate field errors and enhance field quality assurance. The anchors are extensively tested in ICC-certified labs in the US and at universities in the US and around the world.


The biggest challenge in the field is maintain high quality assurance of the installed anchors. With the Külstoff anchors, you are assured to get the right amount of epoxy in the drilled hole and the correct embedded depth. Our patented specialized equipment is designed to ensure that the loose fibers are fully saturated, without excess rein, and kept straight and undamaged to get the best performance from the anchors.



What makes the külstoff embedded anchors special?





Compared to the conventional raw fiber bundled anchors, the Külstoff precured anchor is a custom shop-fabricated piece. It is designed to be perfectly installed each time with production rates many times higher than those for the bundled fiber anchors.


Follow our installation instructions for consistent quality assurance in the field.



For a technical presentation on the evolution of the Külstoff precured anchor visit the Technical Resources page.



saturating & installing the külstoff embedded anchor is quick and reliable





Külstoff Through-Anchor (or Connector)



When surface mounted FRP is required to be continuous across structural members that interrupt the FRP installation, Külstoff's specially designed through-anchors or connectors (BA-THA) provide an easy solution. Our through-anchors come with all the necessary hardware to work seamlessly with our patented tray to ensure full saturation of the anchor fibers.





(830)832-2383 | 7421 Burnet road, #558, AUSTIN, TX 78757



KÜLSTOFF COMPOSITE PRODUCTS, LLC