New approach could slash cost of ultra-durable concrete by 75%
Researchers have developed a new design strategy for ultra-high-performance concrete (UHPC) that could reduce its cost by up to 75% while maintaining its strength and durability.
Ultra-high-performance concrete (UHPC), a material known for its exceptional durability and resistance to cracking, is significantly more expensive than traditional concrete, largely due to the inclusion of metallic fibers. These fibers, while crucial for the material's flexural strength, can increase costs by as much as 30 times. Now, a team of engineers from Penn State has identified key characteristics that can be optimized to make UHPC more affordable.
Through extensive testing of various UHPC mixtures, including those reinforced with both metallic and nonmetallic fibers, the researchers pinpointed ways to reduce the material's price by up to 75% without compromising its remarkable strength, ductility, and durability. This new design approach could lead to more cost-effective, stronger, and environmentally friendly concrete for global construction applications.
UHPC is vital for constructing large, resilient structures like bridges and coastal defenses. Its high strength and ductility enable accelerated construction methods, where pre-built bridge components are assembled on-site. In these applications, UHPC often serves as a high-strength grout bonding these prefabricated elements, rather than replacing traditional concrete entirely.
The high cost of UHPC is primarily attributed to its metallic fibers, which constitute only about 2% of the material's volume but account for roughly 70% of its expense. Additionally, the commercial availability of UHPC as proprietary, pre-bagged mixtures further inflates its price. The Penn State team explored optimizing fiber content and design, including testing various shapes and sizes of metallic fibers, to achieve similar performance with less material.
Furthermore, the researchers investigated the potential of nonmetallic fibers, such as those made from glass strands, basalt, or polymers reinforced with glass or carbon fibers. While these alternatives may not match the strength of steel fibers, their successful implementation could represent a significant step towards reducing the overall cost of UHPC. The study involved evaluating mixtures based on flowability, compressive strength, tensile strength, ductility, and bond strength.
This development addresses a key barrier to the wider adoption of UHPC: its prohibitive cost. By identifying optimization strategies for fiber reinforcement, researchers are paving the way for more accessible use of this advanced material in critical infrastructure. This aligns with the broader additive manufacturing trend of developing high-performance materials for demanding applications, potentially including aerospace and in-situ resource utilization for space construction.
Edited by the news editor with AI from the original report — please refer to the original source.