How to distinguish the type of finished rolled rebar



In this article, we will explore the methods to distinguish the types of finished rolled rebar. Rebar, also known as reinforcement steel, plays a crucial role in construction projects. It is essential to accurately identify the type of rebar to ensure its compatibility with the specific application. This article aims to provide readers with a comprehensive understanding of the distinguishing characteristics of various types of finished rolled rebar.

1. Distinguishing Based on Surface Characteristics

1.1 Smooth Rebar

Smooth rebar, as the name suggests, has a smooth surface without any visible deformations or patterns. It is commonly utilized in low-stress applications and provides excellent bonding with concrete. Moreover, due to its smooth surface, smooth rebar is relatively easy to bend and shape according to construction requirements.

1.2 Deformed Rebar

In contrast to smooth rebar, deformed rebar has protrusions, ribs, or patterns on its surface. These deformations significantly enhance the bond between the rebar and the surrounding concrete. Deformed rebar is widely used in high-stress applications where structural integrity is crucial. The presence of patterns facilitates improved load-bearing capacity, ensuring the reinforced concrete structure's durability.

1.3 Additional Surface Treatments

Apart from smooth and deformed rebar, there are instances where additional surface treatments are applied to enhance specific characteristics. One such example is epoxy-coated rebar, which provides corrosion resistance, making it suitable for marine or high-humidity environments. Another example is galvanized rebar, where a protective zinc coating is applied to prevent corrosion. These surface treatments offer added durability and extend the service life of the rebar.

2. Distinguishing Based on Grade

2.1 Grade 40 Rebar

Grade 40 rebar is a low-grade steel reinforcement with a minimum yield strength of 40,000 pounds per square inch (psi). It is commonly utilized in small-scale construction projects where lower strength requirements exist. Grade 40 rebar is economically viable and suitable for non-structural applications.

2.2 Grade 60 Rebar

Grade 60 rebar is one of the most commonly used types of rebar. It has a yield strength of 60,000 psi, making it suitable for a wide range of construction projects. Grade 60 rebar is employed in structural applications, including bridges, high-rise buildings, and heavy-load structures.

2.3 Grade 75 Rebar

For projects that demand higher strength, grade 75 rebar is a suitable choice. With a minimum yield strength of 75,000 psi, it offers superior tensile strength and structural integrity. Grade 75 rebar is often used in large-scale infrastructure projects, such as highways, dams, and industrial facilities.

3. Distinguishing Based on Markings

3.1 Manufacturer's Markings

Rebar manufacturers typically provide specific markings on the surface to indicate the grade and other essential information. These markings consist of raised characters or symbols that help distinguish different types of rebar. Understanding the manufacturer's markings is crucial to ensure the correct selection and usage of rebar in construction projects.

3.2 ASTM Designations

The American Society for Testing and Materials (ASTM) provides standardized designations for various types of rebar. These designations specify the properties and characteristics of the rebar, aiding in its identification and selection. Familiarity with ASTM designations assists construction professionals in determining the appropriate rebar for their specific project requirements.

3.3 Size and Weight Identification

Besides markings and designations, the physical characteristics of rebar, such as size and weight, can act as distinguishing factors. Different types of rebar have specific dimensions and weights that are used to classify them. Understanding these measurements aids in identifying the type of finished rolled rebar accurately.

4. Distinguishing Based on Material Composition

4.1 Carbon Steel Rebar

Carbon steel rebar, also known as black rebar, is the most common type of rebar available in the market. It is primarily composed of carbon and iron, making it cost-effective and versatile. Carbon steel rebar is suitable for various construction applications where high strength is not the primary concern.

4.2 Stainless Steel Rebar

Stainless steel rebar possesses excellent corrosion resistance properties, making it ideal for structures exposed to harsh environmental conditions. Its composition includes chromium, which provides enhanced durability. Stainless steel rebar is commonly used in coastal areas, wastewater treatment plants, and chemical industries.

4.3 Fiberglass Rebar

Fiberglass rebar, also known as GFRP (Glass Fiber Reinforced Polymer) rebar, offers unique advantages due to its non-metallic composition. Its exceptional resistance to corrosion, electromagnetic properties, and lightweight characteristics make it a suitable choice for infrastructure projects, docks, and bridges.


This article has presented various methods for distinguishing the types of finished rolled rebar. By examining surface characteristics, grade specifications, markings, and material composition, construction professionals can accurately identify the type of rebar needed for their specific projects. It is crucial to consider these distinguishing factors to ensure the successful implementation of reinforced concrete structures. Future research may focus on developing innovative methods to further enhance the identification and performance characteristics of rolled rebar for construction applications.