Tokyo Tsukasa International Co., Ltd. and Oriental Shiraishi Co., Ltd. have jointly developed a prefabricated PC (prestressed concrete) bridge deck "CFCC slab" made of CFCC® carbon fiber composite cables. The product has passed all the tests related to structural performance, completed the wheel load running fatigue test, and was laid on the actual bridge, entering the actual application stage.
In recent years, in the new laying and reconstruction of steel bridge decks, in order to shorten the construction period, increase durability and improve production efficiency, the use of prefabricated PC slabs has gradually increased. "CFCC slab" is a kind of prefabricated PC slab, which uses carbon fiber composite cable to introduce prestress in the bridge deck support direction and the bridge axial direction. In addition, the use of short-fiber reinforced concrete reduces reinforcement materials other than prestressed tendons and reduces costs.
Because carbon fiber composite cable is a corrosion-resistant material, there is no need to add an anti-corrosion coating to the bridge deck used in saline-alkali environments to protect traditional steel bars. In addition, when making concrete components, bridge decks using traditional steel bars need to use the post-tensioning method, which will leave metal prestressing tendons at the end, while using "CFCC slab" will not leave a metal fixed structure when completed. From the perspective of ensuring durability, reliability, and full life cycle (LCC), "CFCC slabs" can be used in harsh saline-alkali environments, such as near the coast or in areas where antifreeze is sprayed.
"CFCC slab" reduces the use of prestressed tendons by using short fiber reinforced concrete, however, compared with traditional two-way PC bridge decks using steel plates and steel bars, both in terms of bending fracture properties (yield strength, toughness) and shear strength , Performance is not inferior. In addition, in the wheel load running fatigue test, the bridge deck did not break even when a load equivalent to about 300 times the index value of 100 years of service life was applied.
"CFCC slabs" are about 6% lighter than traditional slabs of the same thickness, making it possible to optimize the design of bridge slabs at anti-skid holes, drainage ditches, etc. that may cause bridge decks to age due to liquid penetration. Taking a bridge with a length of 240m in saline-alkali area as an example, the use of "CCFC slab" for the bridge deck renovation project can reduce the workload by about 15% compared with the ordinary one-way PC bridge deck. But overall construction costs will increase by 13% to 22%.
The infrastructure also suffers from the same aging issues as bridge decks. "CCFC slabs" also have their uses in the areas of infrastructure reinforcement and transformation.