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MAPEI Corporation has expanded its portfolio of high-performance admixtures with the introduction of Mapefibre ST 50 Twisted, a state-of-the-art macro-synthetic fiber designed to enhance the durability, strength and performance of conventional concrete, pre-cast concrete
and shotcrete applications.

Composed of a specialized blend of polypropylene and polyethylene resins, Mapefibre ST 50 Twisted
provides superior reinforcement by increasing concrete’s ductility, tensile strength and residual
strength – ensuring long-term durability even in the most demanding environments. Unlike
traditional steel reinforcement, these synthetic fibers do not corrode, making them ideal for use in
aggressive environments where resistance to alkalis and moisture-induced deterioration is critical.

“With Mapefibre ST 50 Twisted, we’re delivering a next-generation fiber reinforcement solution that
improves performance while offering significant cost and labor advantages,” said Andrew Fulkerson,
MAPEI Corporation’s Product Line Manager for Admixtures for Concrete. “By reducing plastic
shrinkage, cracking and the need for welded wire mesh or rebar in certain applications, this fiber
provides contractors with a more efficient, reliable and durable concrete solution.”

Engineered for versatility and high performance

Mapefibre ST 50 Twisted meets industry standards, including ASTM C1116-03, ASTM D7508/D7508M20 and ACI 360 R-10. This makes it suitable for a wide range of applications, including industrial and warehouse slabs-on-ground, composite metal decks, bridge decks, concrete pavement, overlays and shotcrete. It is also ideal for precast applications such as septic tanks, burial vaults, pipes and panels.

“Concrete reinforcement technology continues to evolve, and Mapefibre ST 50 Twisted represents
the next step in improving performance, reducing material costs and enhancing ease of use,” said
Gerald LaPier, MAPEI Corporation’s Director of Construction Chemicals. “This fiber solution is
engineered for even distribution within the concrete mix, providing reinforcement from the top to
the bottom of slabs, reducing thermal expansion and contraction effects, and extending the life of
the structure.”

Mapefibre ST 50 Twisted offers multiple advantages that make it a superior choice for concrete
reinforcement. Its corrosion resistance ensures durability even in harsh environments, while its
lightweight nature and ease of handling allow for seamless integration into the mixing process. The
fiber’s special surface treatment enhances bonding with the cementitious matrix, improving overall
concrete performance. Additionally, Mapefibre ST 50 Twisted helps to reduce material costs
compared to welded wire mesh (WWM) and some rebar applications while effectively minimizing
plastic shrinkage and cracking. In shotcrete applications, it significantly decreases equipment wear,
rebound and material waste compared to steel fibers, further optimizing jobsite efficiency.

Sustainable, efficient and built for the future

By replacing traditional steel reinforcement in various applications, Mapefibre ST 50 Twisted
contributes to more sustainable construction practices by lowering overall material usage and
reducing the environmental impact associated with steel production. Additionally, its ease of use
and enhanced performance characteristics make it a smart choice for contractors looking to
improve both efficiency and durability on the jobsite.