Ultra-High-Performance Concrete (UHPC) is a sophisticated class of cementitious composite distinguished by compressive strengths that frequently exceed 150 MPa and augmented tensile capacity achieved through fiber reinforcement (Kravanja et al., 2024).  The extant studies that were reviewed herein were identified through a systematic literature search that employed keywords such as “Ultra-High-Performance Concrete,” “non-proprietary UHPC,” “extreme compressive strength,” and “fiber reinforcement.” From 2005 to 2025, publications were prioritized, with an emphasis on experimental works reporting compressive strengths above 200 megapascals (MPa).

Conventional proprietary UHPC formulations have demonstrated compressive strengths of 150–200 megapascals (MPa) and direct tensile strengths of 5–10 MPa under optimized curing conditions (Graybeal, 2006; Kravanja et al., 2024). However, research over the past two decades has increasingly focused on developing non-proprietary UHPC mixtures capable of surpassing these limits through refined particle packing, the use of supplementary cementitious materials, and innovative curing techniques. This brief communication offers a concise synthesis of experimental UHPC mixtures reported since 2005 that have achieved record mechanical properties, particularly compressive strengths ranging from 200 to 300 megapascals (MPa) and tensile strengths nearing 15 MPa. The emphasis is placed on laboratory-developed, non-commercial mixes, highlighting their mix proportions, curing regimes, and resulting performance.

By consolidating these benchmark achievements, this study offers a focused reference for researchers seeking to advance UHPC mix design, optimize curing strategies, and expand the structural applications of this high-performance material.

UHPC Mix Designs Achieving Ultra-High Strengths

A series of seminal studies have demonstrated the potential of non-proprietary UHPC mixes to exceed conventional strength limits.

Wille et al. achieved compressive strengths above 200 MPa under ambient curing conditions by optimizing particle packing and using 25–30% silica fume with fine quartz powder and low water-to-binder ratios (~0.22). When reinforced with 2–2.5% steel fibers, these mixes reached direct tensile strengths of 12–15 MPa, indicating that fiber geometry and distribution are as critical as fiber dosage (Wille et al., 2011, 2012).

Shin et al. (2018) further advanced the understanding of compressive strength, reporting 341 MPa in a quartz-rich UHPC mortar through multi-stage heat curing (5 days steam + 1 day dry heat) at a very low water-to-binder ratio (~0.17). While tensile performance was not the primary focus of this matrix-only mixture, it did establish an upper limit for compressive strength.

Rong et al. (2020) developed an RPC-type UHPC that achieved 250 MPa compressive strength when specimens were first steam cured and then exposed to 300 °C, illustrating how aggressive post-curing can significantly enhance matrix densification. However, improvements in tensile capacity were modest. Other studies have demonstrated that approximately 30% silica fume replacement, optimized fine sand gradation, and steel fiber reinforcement at approximately 2% volume consistently yield compressive strengths of 200–250 megapascals and tensile strengths of 10–15 megapascals (Kravanja et al., 2024; Ullah et al., 2022).

 In extreme cases, steel fibers have demonstrated compressive strengths exceeding 800 MPa under laboratory confinement (Rong et al., 2020), although these outcomes remain experimental outliers. As demonstrated in Figures 1, 2 and 3, the compressive and tensile strengths of UHPC mixes reported in key studies are illustrated. The key parameters governing record UHPC strength are also demonstrated, as are the effects of curing regimes on UHPC compressive strength.