What is Ultra High Performance Concrete（UHPC)?

About Ultra High Performance Concrete(UHPC)

Ultra High Performance Concrete(UHPC) is an extremely strong and durable type of concrete. According to the American Concrete Institute (ACI) definition, Ultra High Performance Concrete(UHPC) has a minimum compressive strength of 150 megapascals (MPa) and specific requirements for durability, tensile ductility, and toughness.

It achieves these properties by including materials such as cement, silica fume, fine quartz sand, high-range water reducing admixtures, and Copper Coated Steel Fibers.

Features Of Ultra High Performance Concrete(UHPC)

1. High strength:

Ultra High Performance Concrete(UHPC) is incredibly strong when it comes to resisting compression. It typically has a compressive strength ranging from 150 to 250 MPa, which is significantly higher than regular concrete that usually falls within the 20-40 MPa range.

2. Good Tensile strength:

Ultra High Performance Concrete(UHPC) demonstrates remarkable tensile strength, typically ranging from 8 to 12 MPa. This strength is achieved by adding steel fibers to the concrete mix, which enhance its ability to withstand cracking and provide flexibility.

3. High Durability:

Ultra High Performance Concrete(UHPC) is highly durable thanks to its low permeability and resistance to chemical attacks, freeze-thaw cycles, and abrasion.

4. Thin sections:

Ultra High Performance Concrete(UHPC) can be molded into thin sections without sacrificing its strength and durability. This makes it suitable for creating delicate architectural elements and lightweight precast components.

5. Precast applications:

Ultra High Performance Concrete(UHPC) finds extensive use in precast construction, where it is employed to manufacture structural elements like beams, columns, facades, and cladding panels. Its high strength allows for the reduction of material quantities and leads to more efficient designs.

6. Impact resistance:

Ultra High Performance Concrete(UHPC) offers excellent protection against impact loads, making it suitable for applications that require resistance against blast or impact forces. These applications include security barriers, protective structures, and military applications.

Components Of Ultra High Performance Concrete(UHPC)

1. Cementitious Materials:

Ultra High Performance Concrete(UHPC) generally contains a combination of cementitious materials, which provide the binding properties. 

2. Fine Aggregates:

Ultra High Performance Concrete(UHPC) incorporates fine aggregates such as sand, which contribute to the overall density and workability of the concrete.

3. Silica Fume:

Silica fume is a highly reactive pozzolanic material that is commonly added to Ultra High Performance Concrete. It improves the packing of particles, reduces porosity, enhances strength, and enhances the overall performance of the concrete.

4. Fibers:

Ultra High Performance Concrete(UHPC) often includes steel fiber(like copper coated steel fibers, Stainless Steel Fiber) or synthetic fibers(like kuraray PVA fibers) to enhance its tensile strength and toughness. Steel fibers, typically short and discrete, are commonly used to provide post-crack strength and improve the ductility of the concrete. Synthetic fibers, can also be added to enhance durability and reduce cracking.

5. Chemical Admixtures:

Various chemical admixtures may be added to Ultra High Performance Concrete(UHPC) to modify its properties. These can include superplasticizers to improve workability, water reducers to decrease the water content, accelerators to speed up the hydration process, and air-entraining agents to introduce controlled air voids.

6. Water:

Ultra High Performance Concrete(UHPC) requires a precise water-to-cementitious materials ratio to achieve the desired properties. The water used should be clean and free from impurities to prevent any adverse effects on the concrete’s performance.

Advantages Of Ultra High Performance Concrete(UHPC)

1. Super Strong:

Ultra High Performance Concrete(UHPC) is incredibly strong and can handle heavy things without breaking easily.

2. Lasts Long :

Ultra High Performance Concrete(UHPC) stays strong and doesn’t get damaged quickly, so buildings made with it can last a really long time.

3. Doesn’t Get Hurt Easily:

Ultra High Performance Concrete(UHPC) doesn’t get damaged by things like water, chemicals, or bad weather, which means it can stay strong for a long time.

4. Doesn’t Break Easily:

Ultra High Performance Concrete(UHPC) can bend and handle things pushing on it without breaking easily. It can stay in one piece even when it’s being used a lot.

5. Looks Really Nice:

Ultra High Performance Concrete(UHPC) is very smooth and pretty to look at. It can be made into fancy shapes and designs, making buildings look beautiful.

6. Gets Built Quickly:

Ultra High Performance Concrete(UHPC) can get strong faster than regular concrete, so buildings can be built more quickly.

7. Stays Safe in Fires:

Ultra High Performance Concrete(UHPC) doesn’t get damaged easily by fire. It can handle high temperatures and keep buildings safe for a longer time.

8. Helps the Environment:

Ultra High Performance Concrete(UHPC) is good for the Earth because it lasts a long time, so we don’t have to use as much new material. It also helps us save energy because we don’t need to repair or replace things as often.

Various Applications Of Ultra High Performance Concrete(UHPC)

1. UHPC bridge engineering and structural rehabilitation

2. UHPC Facade Panels, Envelope and Clading

3. UHPC joint connections

4. UHPC precast elements

5. UHPC overlay