The article aims to answer the question “What is HPC concrete?”. It will also discuss the components and requirements of high performance concrete (HPC).
Read on to know more:
What is HPC concrete?
High-performance concrete (HPC) is a kind of concrete that is meant to be more durable and, if required, stronger than regular concrete.
When it comes to the basic ingredients, high-performance concrete (HPC) is no different from regular concrete, but the quantities are built to meet specific structural and environmental demands.
Concrete that has a specified compressive strength of 8000 psi (55 MPa) or above is considered high-strength concrete. In order to ensure proper manufacture and testing of the concrete, and to ensure that unique structural design requirements may be necessary, the value of 8000 psi (55 MPa) was chosen as the target strength level for this project.
What components are used to make HP concrete?
Components such as cement sand, gravel, cementitious ingredients including fly ash and silica fume as well as high-range water-reducing chemical admixtures are used to manufacture high-performance concrete (HPC).
The high-performance concrete is more durable and stronger than regular concrete. High-performance concrete hence has a similar composition to traditional cement concrete.
Aside from its high strength, smooth fracture surface and low permeability (as well as discontinuous pores), it has several other qualities that are unique to this kind of concrete. Cementitious materials and chemical admixtures contribute to the low water-to-cement ratio.
The key curing phase for high-performance computing (HPC) begins at the time of installation or completion and lasts for up to three days.
What are the major components used to make HP concrete?
Following are the major components of HP concrete:
Cement
Selecting the right cement for high-performance concrete depends on its chemical and physical qualities. Cement that has a low content of C3A, for example, is the preferred choice for making high-performance concrete, since cements rich in C3A are incompatible with superplasticizers.
Cement with low C3A may be readily regulated in terms of its rheological properties. A certain amount of C3A is essential to cement’s strength, though.
Silica fume
The manufacturing of silicon and silicon alloys generates a waste product known as silica fume. Densified silica fume is the most often utilized type of silica fume, however other forms are also available.
It’s already widely accessible in industrialized nations, where it’s often used in cement. Concrete with a compressive strength of up to 98 MPa may be made without the use of silica fume. Beyond that point, silica fume is absolutely necessary.
HPC with strengths ranging from 63 to 98 MPa may be made more easily using silica fume.
What are the requirements of High performance concrete?
Continue reading the article to understand the requirements of High performance concrete:
In order to attain the high performance and uniformity required by the ACI code, HPC is a specially built concrete that can’t always be produced using ordinary materials and standard mixing, putting, and curing techniques.
For example, its endurance in extreme settings, speed of construction, energy absorption capacity for earthquake-resistant buildings, and repair and retrofitting activities meet most of the shortcomings of traditional concrete.
In this way, HPC is better to traditional cement concrete in that the components are more effective and efficient in contributing to the different qualities of HPC. All high performance concrete has a high strength capacity, however this does not mean all high strength concrete is of the same quality.
It’s also important to keep in mind that not everything has to be met at the same time. High early strength is a necessary attribute for the classification of high performance concrete as HPC. HPC is able to reach its intended strength at a young age because of this feature.
It is possible to acquire a certain level of strength in a short amount of time, or it might take many days. Prestressed concrete may benefit from the high early strength of this concrete, as can precast concrete for quick element manufacturing and precast concrete for rapid form reuse in cold-weather construction, among other applications.
Does HPC have high strength?
Yes, HPC has higher strength as compared to conventional concrete.
Concrete made with high-performance additives has the potential to have a greater compression strength than standard concrete. According to the ACI Code, concrete having a compressive strength more than 40Mpa qualifies as “high strength.”
In concrete facilities, high compressive strength concrete is made with great precision. Special materials may or may not be required for the production of high-strength concrete. In order to get the greatest results, the manufacturer has to be knowledgeable about what influences compressive strength as well as how to alter those aspects.
Many issues arise as a result of traditional concrete’s inability to withstand harsh settings due to its poor durability. Most of these issues with abrasions, freezing/thawing, carbonations, sulfurate attack, blasts, and alkali-aggregate interactions must be addressed if high performance concrete is to give the desired performance over its service life.
What is ultra HPC?
In order to meet the specified requirements for durability, tensile ductility, and toughness, fibers are commonly incorporated into the concrete mix in Ultra-High Performance Concrete (UHPC).
This cementitious concrete material has a minimum specified compressive strength of 17,000 pounds per square inch (120 MPa). Reactive powder concrete, or UHPC, is another name for this kind of concrete (RPC).
Cementitious materials, reactive powders, limestone and/or quartz flour, fine sand (including high-range water reducers), and water are often used to manufacture the material. As a result, the material’s compressive strength may be increased to more than 29,000 pounds per square inch (200 MPa).
The thick, smooth surface provided by the matrix made from fine materials is highly recognised for its aesthetics and its ability to transmit form features to the hardened surface with great precision.
It may produce flexural strengths of up to 7,000 psi (48 MPa) or more when coupled with metal, synthetic, or organic fibers. High carbon steel, PVA, glass, carbon, or a mix of these fibers or others are often utilized in UHPC.
Even after initial breaking, this material’s ductile nature is a first for concrete, and it allows it to bend and withstand flexural and tensile stresses. UHPC’s excellent compressive and tensile qualities make it possible to embed rebar in applications like closing pores between precast pieces with a smaller embedment length while still maintaining a high bond strength.
Self-compacting properties and the absence of reinforcing steel in certain applications make UHPC construction more straightforward. Chloride ion diffusion in the UHPC matrix is less than 0.02 x 10-12 meters per second, due to its dense structure and little linked pore structure.
Low permeability of the material limits the intrusion of dangerous compounds like chlorides, which results in enhanced durability qualities for the material. Pre-mixed UHPC products have been developed by several firms to make UHPC goods more accessible.
ASTM C1856/1856M Standard Practice for Fabricating and Testing Specimens of Ultra High Performance Concrete was produced by the American Society for Testing and Materials and depends on existing ASTM test techniques with adjustments to make them acceptable for UHPC.
Conclusion
Civil engineering projects such as bridges, tunnels, high-rise buildings, highway pavement, and more are benefiting greatly from the use of High Performance Concrete (HPC). HPC is known to make these structures more robust, strong, and durable, and extend their service life.
Somewhat preposterous, the phrase “high performance” refers to this concrete’s materials and proportions, which are precisely designed to have attributes such as high strength and low permeability, for the intended usage of this construction.
There is a difference between high-strength and high-performance concrete, since the qualities of concrete are distinct. To define a “high-performance,” we look at how well the concrete performs, including its durability and strength.
Frequently asked questions (FAQS): What is HPC concrete?
What is HPC concrete?
High-performance concrete (HPC) is a kind of concrete that is meant to be more durable and, if required, stronger than regular concrete.
When it comes to the basic ingredients, high-performance concrete (HPC) is no different from regular concrete, but the quantities are built to meet specific structural and environmental demands.
What is ultra HPC?
In order to meet the specified requirements for durability, tensile ductility, and toughness, fibers are commonly incorporated into the concrete mix in Ultra-High Performance Concrete (UHPC).
This cementitious concrete material has a minimum specified compressive strength of 17,000 pounds per square inch (120 MPa). Reactive powder concrete, or UHPC, is another name for this kind of concrete (RPC).
Does HPC have high strength?
Yes, HPC has higher strength as compared to conventional concrete.
Concrete made with high-performance additives has the potential to have a greater compression strength than standard concrete. According to the ACI Code, concrete having a compressive strength more than 40Mpa qualifies as “high strength.”
What components are used to make HP concrete?
Components such as cement sand, gravel, cementitious ingredients including fly ash and silica fume as well as high-range water-reducing chemical admixtures are used to manufacture high-performance concrete (HPC).
The high-performance concrete is more durable and stronger than regular concrete. High-performance concrete hence has a similar composition to traditional cement concrete.
Aside from its high strength, smooth fracture surface and low permeability (as well as discontinuous pores), it has several other qualities that are unique to this kind of concrete. Cementitious materials and chemical admixtures contribute to the low water-to-cement ratio.
Bibliography
High performance concrete: composition and benefits. Retrieved from: https://www.nbmcw.com/product-technology/construction-chemicals-waterproofing/concrete-admixtures/high-performance-concrete-composition-benefits.html