electricsheepafrica/africa-synth-steel-reinforcement-properties-nigeria

⚠️ Synthetic dataset — Parameterized from published SSA literature, not real observations. Not suitable for empirical analysis or policy inference.

Steel Reinforcement Properties - Nigeria Dataset

Abstract

This dataset provides synthetic but research-grounded data on steel reinforcement bar (rebar) properties commonly used in Nigerian construction. The data encompasses mechanical properties including yield strength, ultimate tensile strength, elongation percentage, and bend test results based on ASTM A615 standards and empirical studies from the Nigerian construction industry. Each record contains detailed information on bar diameter, grade classification, manufacturer source, and corresponding mechanical properties derived from published local research.

Keywords: steel reinforcement, rebar, ASTM A615, yield strength, tensile strength, Nigeria, construction materials, Grade 40/60/75

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1. Introduction

1.1 Background

Steel reinforcement bars (rebar) are essential components in reinforced concrete construction, providing tensile strength to concrete structures that are strong in compression but weak in tension. In Nigeria, the construction industry relies heavily on locally manufactured and imported steel reinforcement bars to meet the growing infrastructure demands. Understanding the mechanical properties of these bars is crucial for structural design, quality assurance, and ensuring compliance with international standards.

1.2 Problem Statement

Significant variability exists in the mechanical properties of reinforcing steel bars available in the Nigerian market. Studies have documented considerable variations between:

• Local manufacturers versus imported rebar
• Different manufacturing processes (billet vs. scrap-based production)
• Brand quality and consistency
• Actual properties versus manufacturer specifications

This variability poses challenges for structural engineers and construction professionals who must ensure that reinforcement meets design requirements and international standards such as ASTM A615.

1.3 Research Objectives

This dataset aims to provide:

1. Comprehensive data on mechanical properties of Nigerian rebar
2. Grade classifications based on yield strength (Grade 40, 60, 75)
3. Manufacturer-specific performance characteristics
4. Test result parameters aligned with ASTM A615 standards

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2. Methodology

2.1 Data Generation Framework

The synthetic data generation follows a research-grounded approach based on published Nigerian studies. Parameters are derived from empirical data on rebar properties from major manufacturers and market surveys conducted across different regions of Nigeria.

2.2 Parameter Evidence Table

Parameter	Source	Value/Range	Evidence
ASTM A615 Standard	ASTM International	Deformed carbon-steel bars	Standard specification for rebar
Grade 40 (280 MPa)	ASTM A615	Yield 280 MPa min	40,000 psi grade
Grade 60 (420 MPa)	ASTM A615	Yield 420 MPa min	60,000 psi grade
Grade 75 (520 MPa)	ASTM A615	Yield 520 MPa min	75,000 psi grade
Yield Strength Range	Ozioko (2016)	250-450 MPa	UMUDIKE JOURNAL OF ENGINEERING AND TECHNOLOGY
Tensile Strength	ASTM A615	1.25× yield min	Ultimate strength requirement
Elongation	ASTM A615	12-20% minimum	Depends on grade
Bend Test	ASTM A615	180° bend	No crack specification
Universal Steel	Lagos market	Ikeja manufacturer	Major Nigerian producer
Prism Steel	Ikirun	Osun State	Major Nigerian producer
Dust Steel	Ilorin	Kwara State	Major Nigerian producer
Local vs Imported	PMC/NCBI study	Lagos market analysis	Significant quality variation
10mm rebar benchmark	Ihom (2024)	Quality assessment	Academia.edu study
Scrap vs Billet	Olaniyi & Adewuyi (2025)	Manufacturing method	GJETA Vol 23(02)

2.3 Test Standards

• ASTM A615/A615M-22: Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement
• ASTM A370: Standard Test Methods and Definitions for Mechanical Testing of Steel Products
• ISO 6935-2: Steel for the reinforcement of concrete - Part 2: Ribbed steel bars

2.4 Grade Classifications

Grade	Yield Strength (MPa)	Yield Strength (psi)	Ultimate Tensile Strength (MPa)
Grade 40	280	40,000	420
Grade 60	420	60,000	620
Grade 75	520	75,000	690

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3. Dataset Description

3.1 Variables

Variable	Type	Description	Range/Values
specimen_id	String	Unique identifier	REBAR-YYYY-NNNNN
bar_diameter_mm	Integer	Nominal diameter	8, 10, 12, 16, 20, 25
grade	Categorical	Steel grade	Grade 40, Grade 60, Grade 75
yield_strength_mpa	Float	Yield strength	250-550 MPa
tensile_strength_mpa	Float	Ultimate tensile strength	400-700 MPa
elongation_percent	Float	Percentage elongation	8-25%
bend_test_angle	Integer	Bend test angle	90, 135, 180
bend_test_result	Categorical	Pass/fail	pass, fail
manufacturer	Categorical	Brand/manufacturer	Universal Steel, Prism Steel, Dust Steel, Imported, Other
manufacturing_method	Categorical	Production method	billet, scrap, mixed
source_location	Categorical	Market/source location	Lagos, Abuja, Port Harcourt, Kano, Ibadan, Owerri
test_standard	String	Applicable standard	ASTM A615, ISO 6935
test_date	Date	Testing date	2020-2025
batch_number	String	Manufacturing batch	Alphanumeric
carbon_content_percent	Float	Chemical composition	0.15-0.40%
sulfur_content_percent	Float	Chemical composition	0.02-0.08%
phosphorus_content_percent	Float	Chemical composition	0.02-0.06%
quality_rating	Categorical	Overall quality	excellent, good, fair, poor
region	Categorical	Geographic region	Southwest, Southeast, North, Niger Delta

3.2 Statistical Distributions

Yield strength follows a normal distribution parameterized by grade:

$${\sigma }_{yield}\sim N({\mu }_{grade},{\sigma }_{grade}^2)\backslash sigma\_\{yield\}\; \backslash sim\; N(\backslash mu\_\{grade\},\; \backslash sigma\_\{grade\}^2)$$

Grade-Specific Parameters:

Grade	Mean Yield (MPa)	Std Dev (MPa)	Sample Size
Grade 40	295	25	Common
Grade 60	445	35	Most common
Grade 75	540	45	Limited use

3.3 Manufacturer Quality Variations

Manufacturer	Location	Typical Quality	Consistency
Universal Steel	Ikeja, Lagos	Good	High
Prism Steel	Ikirun, Osun	Good	Medium
Dust Steel	Ilorin, Kwara	Fair	Medium
Imported	Various	Excellent	High

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4. Source Attribution

4.1 Primary Research Sources

1. Ozioko, H.O. (2016). "Experimental Investigation of the Properties of Reinforcing Steel Bars (Rebars) in the Nigerian Market." UMUDIKE JOURNAL OF ENGINEERING AND TECHNOLOGY, Michael Okpara University of Agriculture Umudike. DOI: 10.9790/1684-1604024952

2. Ihom, A.A. (2024). "Quality Assessment of 10mm Diameter Reinforcing Steel Bars in the Nigerian Construction Industry." Academia.edu Research Publications.

3. Jibrin, M.K. & Ejeh, J.I. (2013). "Effect of Rebar Quality on the Structural Performance of Reinforced Concrete Elements." International Journal of Engineering and Research Technology (IJERT), Vol 2, Issue 33. DOI: 10.17577/IJERTV2IS3305

4. Olaniyi, O.T. & Adewuyi, A.R. (2025). "Comparative Analysis of Scrap-Based vs Billet-Manufactured Rebar Properties in Nigeria." Global Journal of Engineering and Technology Advances, Vol 23(02). DOI: 10.30574/gjeta.2025.23.2.0150

5. Ani, E.C. & Oye, D.N. (2015). "Data of the Properties of Rebar Steel Brands in Lagos, Nigerian Market." Proceedings of the International Conference on Chemical and Environment Engineering.

6. Obi, O.F. & Onah, H.N. (2019). "Evaluation of Mechanical Properties of Locally Manufactured Reinforcing Bars in Nigeria." Nigerian Journal of Technology, 38(2), 412-420.

4.2 Standards Referenced

• ASTM A615/A615M-22: Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement
• ASTM A370-22: Standard Test Methods and Definitions for Mechanical Testing of Steel Products
• ISO 6935-2:2020: Steel for the reinforcement of concrete - Part 2: Ribbed steel bars
• NIS 117:2004: Nigerian Industrial Standard for Steel Reinforcement

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5. Usage Examples

5.1 Loading the Dataset

from datasets import load_dataset

dataset = load_dataset("electricsheepafrica/steel-reinforcement-properties-nigeria")

5.2 Filtering by Grade

# Get Grade 60 rebar data
grade_60 = dataset.filter(lambda x: x['grade'] == 'Grade 60')

5.3 Classification Example

from sklearn.model_selection import train_test_split
from sklearn.ensemble import RandomForestClassifier

X = dataset['train'].remove_columns(['quality_rating', 'specimen_id'])
y = dataset['train']['quality_rating']

X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2)
model = RandomForestClassifier()
model.fit(X_train, y_train)

5.4 Regression Example - Predicting Yield Strength

from sklearn.ensemble import GradientBoostingRegressor

features = ['bar_diameter_mm', 'grade', 'manufacturer', 'carbon_content_percent']
X = dataset['train'][[f for f in features if f != 'yield_strength_mpa']]
y = dataset['train']['yield_strength_mpa']

model = GradientBoostingRegressor()
model.fit(X, y)

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6. Limitations and Caveats

1. Synthetic Data: While parameters are research-grounded, data is synthetically generated and not from actual laboratory tests
2. Regional Focus: Primarily reflects Nigerian market conditions; may not generalize to other West African contexts
3. Limited Grade 75 Data: Grade 75 rebar is less commonly used in Nigeria and has limited empirical data
4. Manufacturer Variability: Quality data for smaller manufacturers is limited
5. Not for Certification: Should not be used for actual structural design or material certification

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7. License

Creative Commons Attribution 4.0 International (CC BY 4.0)

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8. Citation

@dataset{steel_reinforcement_nigeria,
  author = {Electric Sheep Africa},
  title = {Steel Reinforcement Properties - Nigeria Dataset},
  year = {2025},
  publisher = {HuggingFace},
  doi = {10.57967/hf.0005},
  url = {https://huggingface.co/datasets/electricsheepafrica/steel-reinforcement-properties-nigeria}
}

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Dataset Version: 1.0
Last Updated: February 2026
Total Records: 10,000 (across 3 scenarios)