Concrete testing is a fundamental aspect of civil engineering projects in Kenya, ensuring that concrete used in structures meets the required quality, strength, and durability standards. Accurate testing safeguards public safety and enhances the longevity of infrastructure such as roads, bridges, and buildings. Professionals working in county government offices, construction firms, and consulting engineering companies rely on these tests to verify that concrete mixes conform to design specifications and environmental conditions specific to Kenya.

2.1 Concrete Tests

Concrete tests assess various properties of fresh and hardened concrete, such as workability, strength, durability, and density. These tests help engineers and quality control technicians determine if the concrete mix is suitable for specific applications and complies with Kenyan standards like BS 882 and KEBS guidelines.

2.1.1 Workability Tests

Workability tests measure the ease with which concrete can be mixed, placed, compacted, and finished without segregation or bleeding. In Kenya, where construction often occurs in varied climatic and logistical conditions, workability affects the efficiency of concrete placement in sites such as Nairobi County office buildings and rural road projects.

Importance of Workability in Concrete

• Ease of Placement: Workable concrete flows well into formwork and around reinforcement without excessive effort, reducing labor costs and project delays.
• Compaction Efficiency: Proper workability ensures adequate compaction, minimizing voids and improving strength and durability.
• Surface Finish Quality: Concrete with appropriate workability produces smooth, defect-free surfaces, essential for aesthetic and functional requirements in hotels and hospitals.
• Segregation Prevention: Balanced workability prevents the separation of coarse aggregates from the cement paste, maintaining uniformity in the mix.
• Adaptability to Conditions: Workability must be adjusted for temperature and humidity variations common in Kenya to avoid premature setting or excessive slump.

Factors Affecting Workability

• Water-Cement Ratio: Higher water content increases workability but may reduce strength and durability.
• Aggregate Size and Shape: Rounded aggregates improve flow, while angular aggregates reduce workability.
• Mix Proportions: Cement content and admixtures influence the cohesiveness and flow characteristics.
• Temperature: High ambient temperatures in regions like Mombasa accelerate setting, reducing workability time.
• Mixing Time: Adequate mixing ensures uniform distribution of components, impacting consistency.

Common Workability Tests

• Slump Test: Measures consistency and flow of fresh concrete.
• Vee-Bee Test: Assesses the time for concrete to change shape under vibration.
• Flow Table Test: Evaluates flowability by measuring spread diameter on a table.

2.1.2 Slump Test

The slump test is the most widely used method to assess the workability of fresh concrete on Kenyan construction sites. It provides a quick, inexpensive measure of consistency, indicating if the mix is too dry or too wet for effective placement.

Equipment for the Slump Test

Name	Specification	Use
Slump cone	Steel frustum, 300 mm high, 200 mm bottom diameter, 100 mm top diameter, with foot rests and handles	Moulding the concrete sample
Tamping rod	Steel rod 16 mm diameter, about 600 mm long, rounded end	Compacting each layer
Base plate	Rigid, flat, non-absorbent plate	Providing a level surface for the test
Measuring rule	Steel rule graduated in millimetres	Measuring the slump
Scoop	Small steel scoop	Filling the cone

Procedure for Slump Test

1. Prepare Equipment: Use a standard slump cone (300 mm height, 200 mm base diameter) cleaned and moistened.
2. Fill the Cone: Place concrete in three layers, each approximately one-third the cone height.
3. Compact Each Layer: Rod each layer 25 times with a tamping rod to remove air pockets.
4. Remove the Cone: Lift the cone vertically upwards carefully without disturbing the concrete.
5. Measure Slump: Measure the vertical distance the concrete subsided from the original cone height.

Interpretation of Slump Values

• 0–25 mm: Very low workability, suitable for roller-compacted concrete.
• 25–50 mm: Low workability, used in foundations and pavements.
• 50–100 mm: Medium workability, common for beams and columns.
• 100–150 mm: High workability, suitable for heavily reinforced sections.
• Above 150 mm: Excessive workability, risk of segregation and bleeding.

Types of Slump

• True slump: The concrete subsides evenly and keeps its shape, which is the only type that gives a valid result.
• Shear slump: One side of the concrete shears off and slides down, indicating a lack of cohesion, and the test should be repeated.
• Collapse slump: The concrete collapses completely, indicating a very wet or very high-workability mix.
• Zero slump: The concrete does not subside at all, indicating a very stiff mix for which the Vee-Bee test is more suitable.

Limitations of Slump Test

• Not Suitable for Very Dry or Very Wet Mixes: Cannot accurately measure workability of zero-slump or very fluid concrete.
• Subjective Measurement: Operator skill affects accuracy.
• No Direct Correlation to Strength: Slump indicates consistency but not mechanical properties.

Example: the site engineer on a classroom block for a secondary school in Embu rejected a load of concrete with a slump of 180 mm when the specification required 50 mm to 75 mm, because the extra water added by the driver would have weakened the slab.

2.1.3 Vee Bee Test

The Vee-Bee test is used to measure the workability of stiff concrete mixes that are not suitable for the slump test, particularly in hot and dry Kenyan conditions where low-slump concrete is common.

Principle of Vee-Bee Test

The test measures the time taken for a concrete sample to change shape from a cone to a cylinder under vibration, indicating its flowability and cohesiveness.

Testing Procedure

1. Fill the Vee-Bee Cylinder: Place concrete into the standard Vee-Bee mold.
2. Compact the Concrete: Rod the mix to remove air voids.
3. Apply Vibration: Place the cylinder on the vibrating table.
4. Start Timer: Begin timing as vibration starts.
5. Observe Shape Change: Stop timing when the concrete changes from cone to cylindrical shape.
6. Record Vee-Bee Time: The elapsed time in seconds represents workability.

Significance of Vee-Bee Time

• Short Time: Indicates high workability and flowability.
• Long Time: Suggests low workability or stiff mix.
• Used for Quality Control: Helps adjust mix proportions on sites like county government road construction to achieve desired consistency.

2.1.4 Flow Table Test

The flow table test is used to evaluate the flowability of concrete, particularly for mixes with high workability such as self-compacting concrete or concrete used in heavily reinforced sections in urban Nairobi construction projects.

Test Equipment Specifications

Name	Specification	Use
Flow Table	Round table 70 cm diameter, hinged at one side	Measures spread of concrete after jolting
Flow Cone	Steel cone 10 cm diameter	Measures flow time for very fluid mixes

Procedure for Flow Table Test

1. Fill the Cone: Place concrete in the cone in two layers.
2. Compact Each Layer: Rod each layer 25 times.
3. Lift the Cone: Remove the cone vertically.
4. Jolt the Table: Lift and drop the flow table 15 times in 15 seconds.
5. Measure Spread Diameter: Measure average diameter of concrete spread.

Interpretation of Flow Diameter

• Less than 250 mm: Low flowability, may require adjustment.
• 250–350 mm: Moderate flow, suitable for most structural concrete.
• Above 350 mm: High flowability, risk of segregation.

2.1.5 Strength Tests

Strength tests determine the mechanical properties of hardened concrete, essential for structural safety in Kenyan infrastructure projects like hospitals and commercial buildings. These tests confirm whether concrete meets design requirements under various loads.

Samples are cast from the concrete as it is placed, cured under standard conditions and tested at set ages, usually 7 and 28 days, and the results are compared with the specified characteristic strength. Example: the resident engineer on a SACCO's office block in Nyeri required three cubes to be tested at 7 days and three at 28 days for every 25 m³ of concrete placed, so that weak batches could be traced to specific slabs and columns.

Main Strength Tests Compared

Test	Specimen	Property measured	Typical use of result
Compressive strength test	150 mm cubes or 150 × 300 mm cylinders	Resistance to crushing	Acceptance of structural concrete
Flexural strength test	Beams, typically 100 × 100 × 500 mm or 150 × 150 × 750 mm	Resistance to bending (modulus of rupture)	Pavement and slab design
Split tensile strength test	150 × 300 mm cylinders	Indirect tensile strength	Assessing cracking resistance

2.1.6 Compressive Strength Test (Cube and Cylinder Tests)

Compressive strength is the most critical parameter for concrete quality control, indicating the maximum load concrete can withstand before failure.

Importance of Compressive Strength

• Structural Safety: Ensures that beams, columns, and slabs can support design loads.
• Quality Control: Validates mix proportions and curing conditions.
• Contract Compliance: Confirms adherence to specifications required by clients such as banks and universities.
• Predicts Durability: Higher strength usually correlates with longer service life.
• Basis for Mix Design: Guides proportioning of materials for future batches.

Equipment for Cube Testing

Name	Specification	Use
Cube moulds	Steel or cast iron moulds, 150 mm internal size, with base plates	Casting test cubes
Tamping bar	Steel bar with 25 mm square ramming face	Compacting each layer
Curing tank	Water tank maintained at about 20 °C ± 2 °C	Curing cubes until testing
Compression testing machine	Hydraulic machine, typically 2,000 kN to 3,000 kN capacity, calibrated	Crushing cubes and recording failure load

Testing Procedure for Cubes

1. Casting: Fill 150 mm cube molds with fresh concrete in three layers.
2. Compaction: Rod each layer 25 times to remove air voids.
3. Curing: Demold after 24 hours and cure in water at 20°C until test date.
4. Testing: Place cube in compression testing machine.
5. Load Application: Apply load at a uniform rate until failure.
6. Record Maximum Load: Calculate compressive strength.

Formula for Compressive Strength

Compressive Strength (N/mm²) = Maximum Load (N) / Cross-sectional Area (mm²)

Example:

Maximum Load = 450,000 N
Cross-sectional Area = 150 mm × 150 mm = 22,500 mm²

Compressive Strength = 450,000 / 22,500
= 20 N/mm²

Differences Between Cube and Cylinder Tests

• Shape: Cubes are 150 mm cubes; cylinders typically 150 mm diameter and 300 mm height.
• Strength Values: Cylinder strengths are generally 80-85% of cube strengths.
• Usage: Cubes are common in Kenya for routine testing; cylinders are preferred in some international contexts.

2.1.7 Flexural Strength Test

Flexural strength measures the ability of concrete to resist bending forces, critical in slabs, pavements, and beams subjected to bending moments.

Significance of Flexural Strength

• Resistance to Cracking: High flexural strength reduces the risk of cracks under loads.
• Load Distribution: Ensures even load transfer in structural elements.
• Durability Indicator: Flexural strength correlates with the toughness of concrete.
• Design Parameter: Used in pavement and bridge deck design.
• Quality Control: Detects poor concrete mix or curing issues.

Testing Procedure

1. Specimen Preparation: Cast beams (e.g., 100 mm × 100 mm × 500 mm).
2. Curing: Cure specimens under controlled conditions.
3. Test Setup: Place beam on two supports spaced at a fixed length.
4. Load Application: Apply load through two loading points placed at the third points of the span until failure.
5. Record Load and Deflection: Measure maximum load sustained.
6. Calculate Flexural Strength.

Formula for Flexural Strength

Flexural Strength (N/mm²) = (P × L) / (b × d²)

Where:
P = Maximum load (N)
L = Span length (mm)
b = Width of specimen (mm)
d = Depth of specimen (mm)

Worked Example: Flexural Strength

A 100 mm × 100 mm × 500 mm beam tested on a 400 mm span with third-point loading fails at a load of 12,000 N.

Flexural Strength = (P × L) / (b × d²)

Flexural Strength = (12,000 × 400) / (100 × 100²)

Flexural Strength = 4,800,000 / 1,000,000

Flexural Strength = 4.8 N/mm²

2.1.8 Split Tensile Strength Test

The split tensile test evaluates the tensile strength of concrete indirectly, important for assessing cracking potential in slabs and pavements in Kenya.

Importance of Tensile Strength

• Crack Resistance: Tensile strength limits crack propagation under tensile forces.
• Structural Integrity: Critical for concrete elements exposed to bending and tension.
• Material Characterization: Complements compressive strength data.
• Design Input: Used in reinforced concrete design calculations.
• Durability Assessment: Lower tensile strength can lead to early deterioration.

Testing Procedure

1. Specimen Preparation: Use cylindrical specimens (150 mm diameter, 300 mm length).
2. Curing: Cure specimens similarly to compressive strength samples.
3. Positioning: Place cylinder horizontally in testing machine.
4. Load Application: Apply compressive load along the length until failure.
5. Failure Observation: Crack will develop along the vertical diameter.
6. Record Maximum Load: Calculate tensile strength.

A compression testing machine (Source: Road_Construction_Materials_ (1))

Formula for Split Tensile Strength

Split Tensile Strength (N/mm²) = (2 × P) / (π × d × l)

Where:
P = Load at failure (N)
d = Diameter (mm)
l = Length (mm)

Worked Example: Split Tensile Strength

A cylinder 150 mm in diameter and 300 mm long fails at a load of 200,000 N.

Split Tensile Strength = (2 × P) / (π × d × l)

Split Tensile Strength = (2 × 200,000) / (3.1416 × 150 × 300)

Split Tensile Strength = 400,000 / 141,372

Split Tensile Strength = 2.83 N/mm²

2.1.9 Durability Tests

Durability tests assess concrete’s ability to withstand environmental and chemical attacks over time, crucial for infrastructure in coastal and industrial areas of Kenya.

Most durability problems start when water and dissolved chemicals penetrate the concrete, so durability tests mainly measure how easily liquids and ions enter it and how the concrete reacts to aggressive substances. Example: the design team for a beachfront hotel in Watamu specified chloride permeability and water absorption limits for all concrete, after inspecting older buildings nearby where corroding reinforcement had cracked balconies.

Common Causes of Concrete Deterioration

• Chloride attack: Chlorides from seawater and salty aggregates corrode reinforcement, causing cracking and spalling.
• Sulphate attack: Sulphates in soil and groundwater react with cement compounds, causing expansion and cracking.
• Carbonation: Carbon dioxide reduces the alkalinity of concrete, allowing reinforcement to corrode.
• Acid attack: Acids from industrial effluent and sewage dissolve cement paste.
• Abrasion: Traffic, flowing water and impact wear away concrete surfaces.

2.1.10 Rapid Chloride Permeability Test

This test measures the penetration of chloride ions into concrete, vital for structures exposed to marine environments such as Mombasa port facilities.

Purpose of Test

• Assess Corrosion Risk: Chloride ions accelerate steel reinforcement corrosion.
• Quality Evaluation: Determines permeability related to mix design and curing.
• Service Life Prediction: Helps predict durability in chloride-rich environments.
• Compliance Checking: Meets requirements for coastal construction projects.
• Material Selection: Guides choice of additives and sealants.

Testing Procedure

1. Specimen Preparation: Prepare 50 mm thick concrete discs.
2. Conditioning: Saturate specimens with lime water.
3. Test Setup: Place specimen between two cells containing chloride and sodium hydroxide solutions.
4. Apply Voltage: Apply 60 V DC for 6 hours.
5. Measure Charge Passed: Record total coulombs passed through concrete.
6. Interpret Results: Higher charge indicates higher permeability.

Interpretation of Charge Passed

Charge passed (coulombs)	Chloride ion penetrability
Above 4,000	High
2,000 to 4,000	Moderate
1,000 to 2,000	Low
100 to 1,000	Very low
Below 100	Negligible

2.1.11 Water Absorption Test

Water absorption indicates the porosity of concrete, impacting durability and freeze-thaw resistance in highland areas like Nakuru.

Significance of Water Absorption

• Porosity Indicator: High absorption indicates more pores and weaker concrete.
• Durability Measure: Low absorption correlates with resistance to weathering.
• Quality Control: Ensures concrete is dense and well-compacted.
• Predicts Permeability: Influences chloride and sulfate ingress.
• Maintenance Planning: Helps assess potential degradation rates.

Testing Procedure

1. Dry Specimens: Oven-dry concrete samples to constant weight.
2. Soaking: Immerse samples in water for 24 or 48 hours.
3. Surface Drying: Remove surface moisture carefully.
4. Weighing: Record wet weight.
5. Calculate Absorption Percentage.

Worked Example: Water Absorption

An oven-dry concrete core weighs 2,350 g and weighs 2,420 g after soaking.

Water Absorption (%) = ((Wet Weight - Dry Weight) / Dry Weight) × 100

Water Absorption = ((2,420 - 2,350) / 2,350) × 100

Water Absorption = (70 / 2,350) × 100

Water Absorption = 2.98%

2.1.12 Sulphate Resistance Test

Sulphate resistance tests evaluate concrete’s ability to resist chemical attack from sulphate-rich soils or waters, common in parts of Rift Valley.

Importance of Sulphate Resistance

• Prevents Expansion: Sulphate attack causes expansion and cracking.
• Extends Service Life: Resistant concrete lasts longer in aggressive environments.
• Material Selection: Influences choice of cement type and additives.
• Cost Efficiency: Reduces repair and replacement costs.
• Compliance: Ensures standards are met for infrastructure near industrial zones.

Testing Procedure

1. Immerse Specimens: Place samples in sodium sulphate solution.
2. Duration: Expose specimens for several weeks or months.
3. Monitor Changes: Measure weight, length, and strength changes.
4. Evaluate Damage: Assess surface deterioration and cracking.
5. Compare to Control Samples.

2.1.13 Density and Specific Gravity Tests

Density and specific gravity are fundamental properties that influence concrete mix design, affecting strength and durability in Kenyan projects.

Density is the mass per unit volume of concrete, usually about 2,300 kg/m³ to 2,450 kg/m³ for normal-weight concrete, while specific gravity is the ratio of the density of a material to the density of water and has no units. Example: the materials laboratory supporting a dam project for a county irrigation scheme in Makueni used density and specific gravity results of the local aggregates to calculate the exact batch weights for each cubic metre of concrete.

Density = Mass / Volume

Specific Gravity = Density of Material / Density of Water

2.1.14 Unit Weight Test

Unit weight measures the mass per unit volume of concrete, indicating compaction and mix consistency.

Importance of Unit Weight

• Quality Indicator: Higher unit weight suggests better compaction and lower voids.
• Mix Verification: Confirms batch consistency on-site.
• Design Parameter: Used in structural load calculations.
• Material Control: Detects segregation or excess air content.
• Cost Management: Optimizes material usage for economic efficiency.

Testing Procedure

1. Collect Fresh Concrete: Fill container of known volume.
2. Level Surface: Strike off excess concrete.
3. Weigh Container: Determine total weight.
4. Calculate Unit Weight: Subtract container weight and divide by volume.

Worked Example: Unit Weight

A 0.01 m³ container weighs 5.2 kg empty and 29.2 kg when filled with compacted fresh concrete.

Unit Weight = (Full Weight - Empty Weight) / Volume

Unit Weight = (29.2 - 5.2) / 0.01

Unit Weight = 24.0 / 0.01

Unit Weight = 2,400 kg/m³

2.1.15 Specific Gravity Test

Specific gravity compares the density of concrete or its components to water, aiding in quality control of aggregates and cement.

Significance of Specific Gravity

• Material Characterization: Helps identify aggregate types.
• Mix Design: Influences volume calculations.
• Quality Assurance: Detects impurities or lightweight aggregates.
• Durability Assessment: Correlates with strength properties.
• Resource Optimization: Guides selection of materials for concrete.

Testing Procedure

1. Weigh Dry Sample: Record dry weight.
2. Immerse in Water: Weigh suspended sample in water.
3. Calculate Specific Gravity: Use weight measurements to derive value.

Worked Example: Specific Gravity

A dry aggregate sample weighs 2,000 g in air and 1,250 g when suspended in water.

Specific Gravity = Dry Weight / (Dry Weight - Weight in Water)

Specific Gravity = 2,000 / (2,000 - 1,250)

Specific Gravity = 2,000 / 750

Specific Gravity = 2.67

2.1.16 Non-Destructive Testing

Non-destructive testing (NDT) methods evaluate concrete properties without damaging the structure, essential for in-service assessments of bridges and buildings in Nairobi.

NDT is used to check the quality and uniformity of new work, assess existing structures before alterations, locate defects, and decide where cores should be taken for confirmation. Example: before adding two floors to an existing bank building in Thika, the structural engineer used rebound hammer and ultrasonic pulse velocity tests on all columns, then took cores only from the weakest areas identified.

Advantages of Non-Destructive Testing

• No damage to the structure: Tests can be repeated without weakening members.
• Speed: Many points can be tested quickly over large areas.
• In-situ assessment: The actual concrete in the structure is tested, not separate samples.
• Cost saving: Fewer cores and less repair work are needed.
• Monitoring over time: Changes in condition can be tracked by repeating tests.

Limitations of Non-Destructive Testing

• Indirect results: Most NDT methods estimate strength through correlations rather than measuring it directly.
• Need for calibration: Results should be calibrated against cores or cubes of the same concrete.
• Influence of surface conditions: Moisture, carbonation and surface texture affect readings.
• Operator skill: Trained operators are needed to obtain and interpret reliable results.
• Equipment cost: Some NDT instruments are expensive to buy and maintain.

2.1.17 Rebound Hammer Test

The rebound hammer test estimates surface hardness and indirectly the compressive strength of concrete.

Principle of Rebound Hammer

The device measures the rebound of a spring-driven hammer impacting the concrete surface; higher rebounds indicate harder, stronger concrete.

Usage Procedure

1. Prepare Surface: Clean and smooth test surface.
2. Position Hammer: Hold perpendicular to surface.
3. Release Hammer: Allow it to impact and rebound.
4. Record Rebound Number: Average multiple readings.
5. Interpret Strength: Correlate rebound values to compressive strength.

Good Practice for Rebound Hammer Testing

• Take enough readings: Take at least 9 to 12 readings in each test area, spaced at least 25 mm apart.
• Avoid unsuitable spots: Avoid edges, honeycombed areas, aggregate particles and positions directly over reinforcement.
• Discard outliers: Discard readings that differ greatly from the average before calculating the result.
• Correct for direction: Apply corrections when the hammer is used horizontally, upwards or downwards as advised by the manufacturer.
• Calibrate regularly: Check the hammer on its test anvil before and after use.

2.1.18 Ultrasonic Pulse Velocity Test

This test measures the velocity of ultrasonic pulses through concrete, indicating uniformity and detecting defects.

Significance of Pulse Velocity

• Detects Voids and Cracks: Lower velocity suggests internal flaws.
• Quality Assessment: Evaluates concrete compaction and curing.
• Durability Prediction: Correlates with strength and density.
• In-Situ Testing: Suitable for existing structures.
• Non-Destructive: Does not damage the concrete.

Testing Procedure

1. Place Transducers: Attach transmitter and receiver on opposite sides.
2. Generate Pulses: Transmit ultrasonic waves.
3. Measure Transit Time: Record time taken for pulse to travel.
4. Calculate Velocity: Distance divided by transit time.
5. Interpret Results: Compare with standard values.

Worked Example: Pulse Velocity

The path length through a column is 300 mm and the measured transit time is 70 microseconds.

Pulse Velocity = Path Length / Transit Time

Pulse Velocity = 0.300 m / 0.000070 s

Pulse Velocity = 4,286 m/s = 4.29 km/s

Typical Interpretation of Pulse Velocity

Pulse velocity (km/s)	Concrete quality
Above 4.5	Excellent
3.5 to 4.5	Good
3.0 to 3.5	Medium
Below 3.0	Doubtful

2.1.19 Penetration Resistance Test

Penetration resistance tests measure surface hardness by driving a needle into concrete with a known force, useful for rapid assessment of curing and strength development.

Importance of Penetration Resistance

• Early Strength Estimation: Monitors strength gain during curing.
• Quality Control: Identifies weak spots in slabs and pavements.
• Non-Destructive: Minimal damage to surface.
• Cost-Effective: Quick and simple procedure.
• Field Application: Widely used in busy construction sites.

Testing Procedure

1. Prepare Surface: Ensure clean, smooth area.
2. Position Device: Place penetration needle perpendicular to surface.
3. Apply Force: Drive needle into concrete.
4. Measure Penetration Depth: Record depth or resistance.
5. Correlate with Strength: Use charts to estimate compressive strength.

Chapter Summary

This chapter provides a comprehensive overview of concrete testing, beginning with various concrete tests that assess workability, strength, durability, density, and non-destructive properties. Workability tests such as the slump, Vee Bee, and flow table tests evaluate the ease of concrete placement, while strength tests including compressive, flexural, and split tensile strength determine the load-bearing capacity of concrete specimens. Durability tests like rapid chloride permeability, water absorption, and sulphate resistance assess the concrete’s ability to withstand environmental factors. The chapter also covers density and specific gravity tests that help characterize concrete materials. Non-destructive testing methods such as rebound hammer, ultrasonic pulse velocity, and penetration resistance provide insights into concrete quality without damaging the structure. It further explores testing tools and procedures for concrete materials, aggregates, and cement, detailing physical, mechanical, chemical, and soundness properties through various standardized tests. Finally, the chapter addresses concrete curing methods, test analysis and reporting, and the maintenance of concrete testing equipment to ensure reliable and accurate results in construction quality control.

Am I competent?

At the start of this chapter we promised you would be able to:

• Identify the right sources of construction materials based on the job requirements.
• Obtain sampling procedures that match the material specifications needed for the job.
• Correctly assemble all the sampling tools and equipment required for the task.
• Carry out sampling safely and accurately, following the specific job instructions.
• Store samples properly while waiting for analysis, according to job standards.
• Maintain testing equipment correctly to ensure it works well and lasts longer.

Tick each one you can genuinely do.

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