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Carbon fiber is strands of fiber made originally from Nylon fiber, then baked to 3000 degrees to change its chemical form to become a much stronger compound...carbon fiber. Carbon fiber is exceptionally strong for its size and weight. When the strands of carbon are woven or placed parallel with each other, they become exponentially stronger than many other materials. Fortress carbon fiber, with a cross weave of Kevlar, has been tested to be 10 times stronger than steel in a tension application, meaning being pushed, not compressed. Picture on right shows Fortress carbon fiber being installed..................................>>>
Carbon fiber will not stretch and when it is bonded to a bare or properly prepared concrete surface and it will not delaminate or stretch once bonded to the wall or surface. When tested to failure Fortress carbon fiber endured a force ten times normally generated on a basement wall. See this video of the actual testing. http://expertbasementrepair.com/carbon-fiber-structural-integrity-video Carbon fiber composites are as high-tech as you can get today. The new Dreamliner aircraft, space shuttles, boat masts, racing bicycles, racing cars, bullet-proof vests are all made from this modern day miracle composite. Carbon fiber is frequently used for repairs to concrete bridges and commercial and industrial concrete structures. Carbon fiber has been used for more than 15 years by industry and recently has moved into residential repair and stabilization as the production costs have diminished.
Fortress carbon fiber products now routinely replace Steel I beams, wall anchors, and grip-tite anchors for most basement wall repairs. The advantages of carbon fiber over these older technologies is well documented...just ask any structural engineer. A cracked and bowing basement wall is a real potential problem most of the time. This is an indication of a poor drainage issue with soil conditions outside the wall. If the condition is not corrected the wall will usually continue to crack and bow and move inward over time. The amount of time will vary greatly depending upon a variety of site conditions.
The following is additional information on most of the methods available to stabilize your wall and the average costs associated with them. Most interior stabilization does not require outside excavation to releive wall pressure:
First of all we are talking about cement block walls. You must be sure the wall is being pushed inward and not settling. This inward movement generally results in a horizontal crack along the entire wall with stairstep cracking at the corners, and sometimes stair steeping on the adjacent walls. Vertical cracking from floor to ceiling, especially on two adjacent walls is usually settlement...where the foundation is allowing the wall to sink and settle. Carbon fiber is not designed to stabilize wall and foundation settlement. Proper failure analysis is critical for any successful long term repair. Traditional wall stabilization almost always involved the installation of STEEL BEAMS. These beams were often bolted to the floor or set into the floor and cemented in place. They were then attached at the the top of the wall and then attachted to the floor joists with framing. Be aware that not all size steel beams are strong enough to withstand hydrostatic soil pressure loads and sometimes undersized beams are installed to save the contractor money. With steel beams installed in your home you can expect to have a much harder time selling your home later. Rod and grout was the next method to come along. Steel rebar is inserted into the wall and then cemented into place along the length of the rods. There are many skill and knowledge factors required for this work. The rods must be tied into the sill plate and extend below the floor. The grout has to be a specific mix. Rod positioning along the entire wall length is crucial. Simply sticking rebar in the wall and pumping in concrete does little for structural integrity if guidelines are not followed or understood.
Standard steel wall anchors are a steel rod which passes through your block wall and is anchored into the soil outside in the yard. The hole in your wall is then patched, a 20" steel plate is bolted to the rod and tightened with a torque wrench. ( required monthly for warranty ) Full wall anchors do the same thing as the anchors above but have a 6' wall length wall plate mounted on the wall with a nut which requires monthly tightening. Spacing is usually 6" apart but should be closer. You can't finish the walls when you have to tighten the anchor bolts monthly! The appearance of these anchors is almost as daunting as steel beams.
Carbon fiber fabric is the latest entry into the wall stabilization race. Tried, tested and proven to be 10 times stronger than steel beams. ( in tension ) Carbon fiber comes in three versions for basement walls. One version is a fabric mesh which is put on the walls as a large patch. Usually the patch is 2'-4' long and covers the center of the wall. Often these units DO NOT address the higher hydrostatic pressures developed at the bottom two blocks of the wall because they are not long enough. Spacing seems to vary on these. Long term adhesion to the wall has seen to be a problem in the Cleveland Ohio area with some companies. These patches also usually miss the top several rows of block, which is subject to frost breakage.
Carbon fiber plate is very strong. It is manufactured to withstand standard hydrostatic pressure but not differential movement / pressure as it is woven in one direction only. This product requires cleaning with Methyl Ethyl Keytone before installation. 4'spacing is standard. This extra heavy design often doesn't conform well to the bow and displacement of a bowed wall because it is so thick. It is also difficult to confirm 100% wall adheasion because you can't see if all the air voids have been removed after it is installed.
Fortress carbon fiber strength far exceeds any ground / hydrostatic pressure that could ever be developed and is the most versatile of all the carbon products as it is woven with carbon and kevlar and is designed to address differential pressure movement as well as standard hydrostatic pressure. 4' spacing is standard. Structural adhesive epoxy bonds it too the wall and passes through its woven grid pattern to surround and encapsulate the entire strap. Any trapped air or voids can easily be visually identified and removed. There are no VOCs emmited with this product installation.
Because your concrete walls must be fully prepared by grinding before carbon fiber installtion EBR has chosen to utilize a Bosch HEPA VACUUM FILTRATION grinding system. This system will contain dust much better than an inexpensive shop vacuum. This is important if you have asthma or need to keep your furnace running during the basement work.
* From an engineering design, performance and warranty point of view you must stabilize the entire wall length. Should you choose to have EBR perform your wall stabilization with Fortress carbon fiber you will always receive a double lifetime and transferable warranty! Contact us for more information.
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