Concrete, composed of multiple ingredients that transition from a plastic phase to a solid state over time, is prone to cracking. This inherent characteristic demands careful consideration in concrete bridge deck design, mainly because these structures face aggressive environmental and mechanical stressors.
FORTA’s innovative synthetic fiber solutions address this challenge by reinforcing concrete, making it a smarter and more durable choice for bridge construction and repair.
Incorporating synthetic fibers in concrete bridge deck construction significantly enhances performance. Synthetic fibers enhance concrete by distributing tensile loads and reducing the formation of cracks, which often result from plastic shrinkage and thermal stresses. This innovation extends the life span of bridge decks while contributing to their structural integrity from the moment of installation.
Synthetic fibers, like those from FORTA, are dispersed throughout the concrete mix. They act as a three-dimensional reinforcement system, offering several benefits:
FORTA offers several high-performance products for precast concrete bridge decks, concrete bridge deck overlays, and general concrete bridge deck construction:
Several successful projects have utilized FORTA fibers in concrete bridge construction and repair.
This project utilized a high-performance concrete mix incorporating FORTA-FERRO and ECONO-MONO fibers, resulting in a 75% reduction in shrinkage and a 60% decrease in creep without any cracking observed over years of service.
In May 2017, the Minnesota Department of Transportation constructed a bridge deck using 5.0 pounds per cubic yard of FORTA-FERRO to reduce cracking, prevent water intrusion, and freeze-thaw deterioration. This choice effectively saved time and money by allowing the bridge deck to be pumped and placed in a single day.
This project, initially resurfaced in 1997 and further reinforced with 4.0 pounds per cubic yard of FORTA-FERRO fibers in 2001, has shown remarkable durability and crack resistance over the years. It showcases the effectiveness of FORTA products in enhancing the durability and performance of concrete bridge deck overlays.
MnDOT specified fibers be used in 11 bridges being done on I-35W and I-94 from downtown to crosstown in Minneapolis, MN. This is a lengthy project which includes installing new non-fiber concrete on a 50-year old freeway, new ramp access from I-35W south to Lake St. and from I-35W north to 28th St.,and building MnPASS lanes near the downtown bus station at Lake St. for better transit service. In addition, the new pedestrian bridges will be wider and more accessible, congestion will be reduced, and traffic mobility will be increased. FORTA-FERRO macro synthetic fibers were chosen to be used at a dosage of 5.0 lb/cu yd. The concrete was provided by Aggregate Industries and placed by LUNDA Construction Co. For this project, the fibers are required to be a combination blend of micro and macro non-metallic fibers to provide crack control and improve the long-term performance of the bridge decks. The micro fibers are used for controlling the plastic shrinkage cracking, and the macro fibers are used to provide increased residual flexural strength throughout the concrete.
4 years later, this project remains in great condition due to the characteristics and benefits of FORTA reinforcement fibers.
FORTA is a trusted partner for engineers, architects, and contractors seeking innovative bridge construction and repair solutions. Our team of engineers is equipped to provide guidance from design and conversion to completion. Contact us today to discuss how our fiber-reinforced concrete solutions can enhance your concrete bridge deck construction projects.
