What is the minimum standard for the cube compressive strength of UHPC?

According to the national standard "Ultra-High Performance Concrete" GB/T 31387, the minimum standard for the 28-day cubic compressive strength of UHPC is 120MPa. This indicator is the key performance threshold that distinguishes UHPC from high-performance concrete (HPC) and ordinary concrete.

In actual engineering, the compressive strength of high-quality UHPC typically far exceeds this standard. Qinglong UHPC products maintain a stable 28-day compressive strength of 135-150MPa, with the coefficient of variation controlled within 5%. For example, in testing for a super high-rise project in Wuhan, 100mm cubic specimens achieved a compressive strength of 142MPa, and the failure pattern exhibited typical ductile characteristics, indicating that the material has a sound microstructure.

Indicator Requirements Specified by the Standard

28-day compressive strength ≥120MPa; strength grades: UHPC120, UHPC130, UHPC150; specimen size of 100mm cube. These are the basic requirements.

Performance Levels of High-Quality Products

High-quality products can reach 150-180MPa; strength coefficient of variation ≤5%; continuous later-age strength growth. These reflect a high-quality level.

Key Factors Affecting Strength

Water-binder ratio controlled at 0.18-0.22; activity of cementitious materials; standardized curing regimes. These factors determine strength.

Relationship Between Strength and Other Properties

It must be balanced with toughness; it is positively correlated with durability; it needs to be coordinated with workability. These relationships require overall consideration.

Compressive strength is a basic indicator, but other properties must also be considered comprehensively. Qinglong UHPC products deliver excellent strength indicators along with balanced development across all properties.