We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Is Concrete Compressive Strength?

By B. Turner
Updated May 17, 2024
Our promise to you
About Mechanics is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At About Mechanics, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Concrete is a building material made from sand, water, gravel, and Portland cement. As this mixture hardens, or cures, it forms a very strong and durable material. Because of its strength and resilience, concrete is widely used to construct buildings, roads, and a variety of other structures. When building with concrete, it is important to understand whether it can stand up to the compressive forces in the structure where its being used. One way to measure this is by testing the concrete's compressive strength, or how well it holds up to the compressive pressures around it.

While concrete contains very few ingredients, the exact mix ratio must be chosen carefully to ensure the concrete will perform as intended. If too much or too little water is added, for example, the cured concrete is likely to crack or show signs of surface damage. In some cases, the wrong mix ratio can lead to structural failure, which may result in serious safety issues.

Installers and independent testing agencies use a number of testing standards to check the integrity of freshly-poured concrete. One of the most widely used benchmarks is a test of concrete compressive strength. This measures the material's ability to withstand compressive forces. For example, a second-floor deck is subject to compressive force from beams positioned above and below the deck. By testing the concrete after it's poured, installers can ensure this floor is strong enough to withstand these forces and keep occupants safe.

The most common testing method for concrete compressive strength requires installers to pour three cylinders from the same mixture used on the structure itself. The three cylinders are placed in tubes or containers and given 28 days to dry before they are sent to testing labs. At the lab, each cylinder is placed in a machine that applies compressive force from above and below the cylinder. Once the cylinders break, or fail, agents measure the amount of strength each cylinder was able to withstand, then compare these results to the specified strength rating for the concrete to see if they match.

People in different parts of the world use different rating systems for measuring concrete compressive strength. In the United States, concrete strength is measured using pounds per square inch, or PSI. A standard concrete mixture used on a sidewalk may measure 3,000 PSI on average, though exact ratings must be determined by a structural engineer. Countries that use the metric system measure this compressive strength using megapascals, or Newtons of force per square meter. A concrete mixture that measures 3,000 PSI is equivalent to approximately 20 megapascals.

Concrete compressive strength should not be confused with tensile strength. Tensile strength measures the ability of concrete to resist lateral forces, or to resist being pulled apart from either side. While concrete has a fairly high compressive strength, it generally has a poor tensile strength. Many installers add reinforcement steel or rebar to improve the tensile strength of concrete. To increase compressive strength, it is often necessary to change the mix ratio or add special hardeners.

About Mechanics is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.

About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.