How to Test Concrete Strength?

Concrete is one of the most widely used construction materials, renowned for its durability and strength. There are several methods to test the strength of concrete, but one of the most efficient and non-destructive techniques is the Swiss Hammer Test, also known as the Schmidt Hammer Test. In this blog, we will explore how to test concrete strength using the Swiss Hammer Test and explain how our company, Skill Stone, can provide this service in Leicester and throughout the UK.

Understanding Concrete Strength

Concrete strength is a measure of its ability to withstand loads without failing. The strength of concrete is typically measured in terms of compressive strength, which is the capacity of a material to withstand loads that reduce size. Testing the compressive strength of concrete is essential for assessing the material’s suitability for various construction purposes.

What is the Swiss Hammer Test?

The Swiss Hammer Test, developed by Ernst Schmidt in the 1950s, is a simple, non-destructive testing method used to evaluate the surface hardness and estimate the compressive strength of concrete. This test is widely used because of its portability, ease of use and quick results.

How the Swiss Hammer Test Works

To perform the Swiss Hammer Test, you need to start by ensuring the concrete surface is clean, smooth and dry. Any loose particles or debris should be removed to obtain accurate results. Before testing, the Schmidt Hammer should be calibrated using a test anvil to ensure accuracy.

Hold the Schmidt Hammer perpendicular to the concrete surface, press the plunger against the surface until the hammer’s mass is released and strikes the plunger. After the mass impacts the plunger, it rebounds, and the hammer’s scale will display a rebound number. This number is an indication of the surface hardness.

Typically, multiple tests are performed on different areas of the concrete surface, and the average rebound value is calculated. The rebound value is then compared to a calibration chart provided by the Schmidt Hammer manufacturer to estimate the compressive strength of the concrete.

The Swiss Hammer Test is a non-destructive method, meaning it does not damage the concrete, making it ideal for assessing the strength of existing structures. The test can be performed quickly and is portable, making it convenient for field testing.

What is RAAC?

Reinforced Autoclaved Aerated Concrete is a form of lightweight concrete used in construction in many buildings between the 1950s and 1990s. RAAC is highly aerated with different material properties to conventional concrete. It is mainly found in roofs, occasionally in floors and walls.

How to identify RAAC concrete?

RAAC panels are light-grey or white in appearance, the underside of the panels will appear smooth. The inside of the planks will appear bubbly, often described as looking like an Aero bar. Unlike traditional concrete, there will not be visible stones (aggregate) in the panels.

Your Local Concrete Testing Experts

At Skill Stone, we understand the importance of accurate and reliable concrete strength testing. We are proud to offer concrete testing services, including the Swiss Hammer Test, in Leicester and throughout the UK.

Our team consists of highly trained and certified professionals with extensive experience in concrete testing. We adhere to stringent quality control measures to provide accurate and dependable results. We prioritise customer satisfaction and work closely with clients to meet their specific needs and requirements. While based in Leicester, our services are available across the UK, ensuring that you have access to quality concrete testing wherever your project is located.

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