What is UHPC?

UHPC is the acronym for 'ultra high performance concrete', in Germany, the material is called UHFB - Ultra Hochfester Beton.

UHPC is the new generation of concretes . Per definition the class of UHPC starts with strength of 120MPa. Our definition is different - it is HIGH PERFORMANCE. We do use our HIGH DEFINITION CONCRETE MATRIX to realize high strength, high flexural strength, high density as well as further positive advantages. 

 

It is an advanced form of concrete known for its exceptional strength, durability, and versatility. UHPC typically consists of a densely packed mixture of fine aggregates, cement, water, and sometimes supplementary materials like silica fume, fibers (such as steel or polymer), and chemical admixtures. These components are carefully proportioned to achieve the desired properties.

 

Some typical characteristic properties of UHPC include:

 

1. High Compressive Strength: UHPC can achieve compressive strengths exceeding 150 MPa (22,000 psi) or even higher, making it much stronger than conventional concrete.

 

2. High Flexural Strength: UHPC exhibits excellent flexural strength, allowing it to withstand bending and tension forces better than traditional concrete.

 

3. Low Permeability: The dense microstructure of UHPC results in low permeability, making it highly resistant to water penetration, chemical attack, and corrosion of embedded steel reinforcement.

 

4. High Durability: UHPC has outstanding resistance to abrasion, freeze-thaw cycles, and chemical exposure, enhancing its long-term durability and service life.

 

5. Reduced Shrinkage: UHPC typically experiences lower shrinkage compared to conventional concrete, minimizing the risk of cracking and improving dimensional stability.

 

6. Excellent Workability: Despite its high strength, UHPC can be formulated to have good workability, allowing for ease of placement and finishing.

 

7. Enhanced Bond Strength: UHPC exhibits strong bond characteristics with steel reinforcement and other materials, leading to efficient transfer of loads and improved structural performance.

 

8. Tailorable Properties: The composition of UHPC can be adjusted to meet specific project requirements, allowing for customization of properties such as setting time, flowability, and curing characteristics.

 

9. Highly Engineered Material: UHPC is often used in specialized applications where superior performance is critical, such as bridge construction, high-rise buildings, precast elements, and infrastructure projects.

 

Overall, the exceptional properties of UHPC make it a preferred choice for demanding engineering applications where strength, durability, and performance are paramount.

 

UHPC advantages

> developed with good and cost-effecive raw materials
> perfect workability
> adaptable from clay-like to self compacting
> high compressive strength
> high flexural strength
> low porosity, no capillary pores
> cost-effective
> sustainable
> available: worldwide

 

UHPC design possibilities

> all kind of colors - also snow-white and dark gray
> from very rough surfaces to a high glossy self-cleaning finish
> no additional coatings are needed
> no limits for forms and shapes
> unit thickness from 2 mm up to meters

 

Applications

  • Structural elements: walls, beams, girders, ...
  • Pre-Cast Elements
  • Pre-Cast Bridge Constructions, ...
  • Infrastructure: Pipes, ...
  • Floor Systems, Tiles, ...
  • Interior and exterior facade panels
  • Interior Design
  • ...

Codes

As our my last update in January 2022, there isn't a universally adopted set of international design rules specifically tailored for Ultra-High Performance Concrete (UHPC). However, several countries and organizations have developed guidelines, specifications, and codes for the design and use of UHPC in various applications. Here are some examples:

 

1. ACI 239R-18: The American Concrete Institute (ACI) published a report titled "Ultra-High-Performance Concrete: An Emerging Technology Report" which provides information on the material properties, design considerations, and applications of UHPC. While not a design code itself, it serves as a valuable resource for engineers and designers working with UHPC.

 

2. fib Bulletin 90: The International Federation for Structural Concrete (fib) has published Bulletin 90 titled "Design recommendations for ultra-high performance fibre-reinforced concrete", which offers guidelines and recommendations for the design of structural elements using UHPC.

 

3. EN 14651: European Standard EN 14651 provides methods for testing the compressive strength of UHPC specimens, but it doesn't include design rules. However, individual countries within Europe may have their own design guidelines or specifications for UHPC.

 

4. JSCE Guidelines for Concrete No. 5: The Japan Society of Civil Engineers (JSCE) has issued guidelines for the design and construction of UHPC structures, including specifications for material properties, mix design, and structural design considerations.

 

5. Canadian Highway Bridge Design Code (CHBDC): Although not specific to UHPC, the CHBDC provides provisions for the design of bridges using high-strength concrete, which may include UHPC in certain applications. 

 

6. Other National Standards: Various countries may have their own national standards or guidelines for the use of UHPC in construction and infrastructure projects. For example, in France, the French Association for Civil Engineering (AFGC) has developed guidelines for the design and implementation of UHPC in bridge construction.

 

It's important to note that while there are guidelines and recommendations available, the design of structures using UHPC often requires a thorough understanding of material properties, structural behavior, and performance considerations. Engineers typically rely on a combination of available standards, research findings, and engineering judgment to design safe and efficient structures using UHPC. As the use of UHPC continues to grow, it's possible that more comprehensive international design codes specifically tailored for UHPC may be developed in the future.