Which Properties Do UHPC's "Three Highs and One Low" Characteristics Refer To?

In the field of UHPC, “three highs and one low” is an incisive summary of its most core and outstanding performance characteristics, specifically referring to “high strength, high toughness, high durability” and “low permeability”. These four properties are interrelated and together constitute the fundamental advantages that distinguish UHPC from traditional concrete. Through 28 years of material application practice, Qinglong Group has come to deeply understand that “three highs and one low” is the key to UHPC's applicability in landmark buildings and infrastructure in harsh environments.

“High strength” is UHPC's entry ticket, mainly reflected in compressive strength and flexural strength. Qinglong UHPC's compressive strength easily exceeds 120MPa and can even reach above 150MPa; its flexural strength also reaches 15-25MPa, ten times or even dozens of times that of ordinary concrete. This ultra-high strength allows component cross-sections to be made thinner and lighter, achieving large-scale prefabrication and a light, elegant architectural aesthetic, as seen in the thin curtain wall panels used in the Shenzhen Yirui Biotech Building project.

“High toughness” is UHPC's revolutionary breakthrough, freeing it from the weakness of traditional concrete's brittleness and susceptibility to cracking. Through uniformly distributed steel fibers bridging cracks, UHPC does not suddenly fracture after reaching peak load, but can maintain a certain residual strength, exhibiting significant ductility. Its flexural toughness and fracture energy indices are extremely high, enabling it to absorb enormous energy with superior impact resistance. This property is crucial in protective engineering, bridge deck paving, and other scenarios that must withstand dynamic loads and impacts.

“High durability” and “low permeability” are two sides of the same coin, jointly ensuring UHPC's long-term performance. Thanks to tightly packed particle gradation and an extremely low water-binder ratio, Qinglong UHPC has extremely low porosity and a very dense structure, resulting in extremely low permeability—it is almost impervious to water and air. This makes it difficult for harmful media in the external environment, such as chloride ions, carbon dioxide, and sulfates, to penetrate, giving it exceptional impermeability, resistance to chloride ion attack, carbonation resistance, and freeze-thaw resistance. In urban renewal projects such as Shanghai Century Plaza, UHPC's long-term durability is an important reason for its selection. Together, these “three highs and one low” forge UHPC's advantages of an ultra-long service life and low maintenance costs.