Who We Are

About NDT East Africa

15+ years of precision Non-Destructive Testing and Structural Audit solutions across East Africa and beyond.

10+

Years of Trust

Our Main Areas of Business

To estimate the in-situ compressive strength of concrete.
To identify/map reinforcement profile on slabs, beams, columns and other structural elements.
To measure concrete cover, re-bar diameter, spacing, etc.
To estimate the uniformity and homogeneity of concrete.
To estimate the quality of concrete in relation to standard requirements.
To identify areas of lower integrity in comparison to other parts.
To detect presence of cracks, voids and other imperfections.
To monitor changes in the structure of the concrete which may occur with time.
To establish the extent of corrosion on prestressed/reinforcement steel.
To establish chloride, sulphate, alkali contents or degree of carbonation.
To establish the condition of grouting in prestressing cable ducts.
To measure Elastic Modulus.

The Science Behind It

Why Non-Destructive Tests

It is important to verify whether concrete structures have achieved their design objectives after the concrete has hardened. It is preferred that any test conducted on hardened concrete should result in minimal or no damage to the structure.

It is important to examine hardened concrete structures for their suitability for intended use. In such cases, Non-Destructive Test methods are used. NDT techniques are increasingly being adopted on concrete structures for the following purposes:

To estimate the in-situ compressive strength of concrete.

To identify/map reinforcement profile on slabs, beams, columns and other structural elements.

To measure concrete cover, re-bar diameter, spacing etc.

To estimate the uniformity and homogeneity of concrete.

To estimate the quality of concrete in relation to standard requirements.

To identify areas of lower integrity in comparison to other parts.

To detect presence of cracks, voids and other imperfections.

To monitor changes in the structure of the concrete which may occur with time.

To establish the extent of corrosion on prestressed/reinforcement steel.

To establish chloride, sulphate, alkali contents or degree of carbonation.

To measure Elastic Modulus.

To establish the condition of grouting in prestressing cable ducts.

NDT Tests range from the completely non-destructive, where there is no damage to the concrete, through those where the concrete surface is slightly damaged, to partially destructive tests, such as core tests and pullout and pull-off tests, where the surface has to be repaired after the test. Non-destructive testing can be applied to both old and new structures. For new structures, the principal applications are likely to be for quality control or the resolution of doubts about the quality of materials or construction. The testing of existing structures is usually related to an assessment of structural integrity or adequacy. In either case, if destructive testing alone is used — for instance, by removing cores for compression testing — the cost may only allow a relatively small number of tests to be carried out on a large structure which may be misleading. Non-destructive testing can be used in those situations as a preliminary to subsequent coring.

Application Scenarios

When Do You Need NDT on Concrete Structures

Typical situations when Non-Destructive Testing of Concrete may be useful include:

Quality control of pre-cast units or construction in situ.

Removing uncertainties about the acceptability of the material supplied owing to apparent non-compliance with specification.

Confirming or negating doubt concerning the workmanship involved in batching, mixing, placing, compacting or curing of concrete.

Monitoring of strength development in relation to formwork removal, cessation of curing, prestressing, load application or similar purpose.

Location and determination of the extent of cracks, voids, honeycombing and similar defects within a concrete structure.

Determining the concrete uniformity, possibly preliminary to core cutting, load testing or other more expensive or disruptive tests.

Determining the position, quantity or condition of reinforcement.

Increasing the confidence level of a smaller number of destructive tests.

Determining the extent of concrete variability in order to help in the selection of sample locations representative of the quality to be assessed.

Confirming or locating suspected deterioration of concrete resulting from overloading, fatigue, external or internal chemical attack or change, fire, explosion, environmental effects.

Assessing the potential durability of the concrete.

Monitoring long term changes in concrete properties and providing information for any proposed change of use of a structure for insurance or change of ownership.

Structural Audit Services

For Structural Audit Services

Ready to verify the integrity of your structure? Our certified team of Engineers and Technicians is available to discuss your NDT and Structural Audit requirements — from first consultation through to detailed reporting.

Get in Touch With Us

☎

Phone

+254 721 414 663

✉

info@ndt-ea.com

📍

Location

Water Sys Plaza, Biashara Street, Nairobi

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FAQ's

Find quick answers to common questions about Non-Destructive Testing — its purpose, applications, methods, and benefits for concrete structures.

FAQ

What is NDT? +

NDT stands for Non Destructive Testing of Concrete. It is a method of testing existing concrete structures to assess their strengths, durability and other structural characteristics without inflicting any damage to the structural elements.

Where do you need NDT on concrete structures? +

Typical situations where NDT may be useful include:

To estimate the in-situ compressive strength of concrete.
To identify/map reinforcement profile on slabs, beams, columns and other structural elements.
To measure concrete cover, re-bar diameter, spacing etc.
To estimate the uniformity and homogeneity of concrete.
To estimate the quality of concrete in relation to standard requirements.
To identify areas of lower integrity in comparison to other parts.
To detect presence of cracks, voids and other imperfections.
To monitor changes in the structure of the concrete which may occur with time.
To establish the extent of corrosion on prestressed/reinforcement steel.
To establish chloride, sulphate, alkali contents or degree of carbonation.
To establish the condition of grouting in prestressing cable ducts.
To measure Elastic Modulus.

When do you need NDT on Concrete Structures? +

Typical situations when NDT may be useful include:

Quality control of pre-cast units or construction in situ.
Removing uncertainties about the acceptability of the material supplied owing to apparent non-compliance with specification.
Confirming or negating doubt concerning the workmanship involved in batching, mixing, placing, compacting or curing of concrete.
Monitoring of strength development in relation to formwork removal, cessation of curing, prestressing, load application or similar purpose.
Location and determination of the extent of cracks, voids, honeycombing and similar defects within a concrete structure.
Determining the concrete uniformity, possibly preliminary to core cutting, load testing or other more expensive or disruptive tests.
Determining the position, quantity or condition of reinforcement.
Increasing the confidence level of a smaller number of destructive tests.

Why use NDT? +

Here are the top reasons NDT is used by so many companies throughout the world:

💰 Savings

NDT allows the material or object being examined to survive the examination unharmed, thus saving money and resources.

🛡 Safety

Almost all NDT techniques (except radiographic testing) are completely harmless to people on site.

⚡ Efficiency

NDT methods allow thorough and relatively quick evaluation of assets, crucial for ensuring continued safety and performance on a job site.

🎯 Accuracy

NDT methods have been proven accurate and predictable — both qualities you want for maintenance procedures meant to ensure the safety of personnel and longevity of equipment.

What are the commonly used NDT methods? +

Here are the eight commonly used NDT methods:

Visual NDT (VT) Ultrasonic NDT (UT) Radiography NDT (RT) Eddy Current NDT (ET) Magnetic Particle NDT (MT) Acoustic Emission NDT (AE) Dye Penetrant NDT (PT) Leak Testing (LT)

What is the visual inspection method? +

Visual inspection is a type of nondestructive testing (NDT) in which a certified technician examines the material for surface-level discontinuities, corrosion or misalignment. Visual inspection is done with the naked eye by closely examining the material, including all its weldments and attachments. Magnifiers, mirrors, and borescopes can help technicians get an even closer look. Some visual inspections are completed with the help of remote viewing.

Visual inspections are completed for a variety of industries, including oil and gas, utility, aerospace, telecom, conventional generation, and renewables. Done in conjunction with other NDT testing methods, you can get a complete picture of the health of your assets, and what steps to take for remediation and repair.

How accurate is visual inspection? +

Visual inspection is how NDT technicians assess the cause and extent of surface-level damage to materials, including cracks, corrosion, and misaligned parts. However, it is important to employ the full range of nondestructive testing methods — which include ultrasonic testing, magnetic particle testing, and liquid penetrant testing — to get a more complete picture of material integrity.