A Quick Guide on Concrete Strength: Factors that Affect Tensile and Compressive Resilience
Strength is quality. Quality is durability and performance. This is true for how people measure the quality of concrete and the structures it supports. Structural concrete plays an invaluable role in our society and the construction of our cities, so the strength of this material is to speak of the quality of our buildings, bridges, and more. For generations now, the process and equipment involved in concrete production continues to be modernized and improved.
So how strong is concrete? The answer depends on various factors. Let’s take a look!
The Key Ingredient for Concrete Strength
When broken down into original components, concrete is a type of paste composed of aggregates. The paste is a compound that is made up of water and Portland cement. The material achieves strength through a chemical reaction that hardens the material. As it dries, concrete achieves its strength, and yet has considerable malleability when it’s still wet. This is part of what makes the material a go-to for many construction projects, as it is relatively easy to manage and highly dependable.
Concrete strength is measured to understand its capacity to perform and withstand harsh conditions. When speaking about concrete strength, people speak about three different types of strength criteria. It has a compressive strength, which indicates a comprehensive strength of the material and is measured in psi. Depending on the application the concrete will be used for, other strengths are taken into account including a degree of flexure, or bending. Tensile strength—also measured in psi—also comes into consideration.
Strong concrete is a result of a process and certain factors:
- Ratio: The ratio of cement and water in the mixture will have an impact on the strength of the material.
- The proportion of materials: The proportion of the key materials (water, cement, aggregates, and air) is important for achieving higher concrete strength.
- Curing: The initial moisture in the concrete will also impact its overall strength. If curing in extreme hot or cold temperatures, the curation process should be supervised. Moisture should be maintained to help the cement hydration process. The hydration process is the key chemical reaction that assures quality in the material. Monitoring of the curing process is especially key in extreme temperatures to ensure evaporation doesn’t happen and prevent the proper curing of the material.
- Mixing: The mixing time of the materials is important to achieving strength. Mixing for too long, however, can also be detrimental. So, the mixing process should be done meticulously and with measure.
- Quality of materials: So just like anything, the final product reflects the quality of its initial materials. For example, the water used in mixing the cement will affect the final product. If there are enough impurities in the water, setting time and strength might be affected. The quality of the aggregates is also an important factor in the final product.
Importance in Degrees and How Strength Matters
Concrete is used in a plethora of construction projects and applications. From walkways to bridges to supporting columns in a high-rise building. Regardless of the application, strength is critical, especially when the concrete is serving a supporting role or is a central component of the construction. There are codes and specifications required depending on the structure.
Some designs require strengths of up to 5,000 to 6,000 psi. When concrete is used as a supporting structure in a multi-story building, for example, the range can be up to 15,000 to 20,000 psi. The minimum for most standard projects, however, is about 2,500 – 3,000 psi.
The compressive strength of the material is tested on day 7 and on day 28. This determines the final psi but is also used to assess any early strength gains.
A Magnified Look at PSI
Concrete strength is measured by psi, or pounds per square inch. This metric refers to a unit of pressure expressed in pounds per square inch. The higher the psi, the stronger the material. This unit is used in Western countries to express the maximum amount of pressure an object can tolerate. A vehicle tire, for example, has a psi. So the number means that’s the maximum pressure that a tire can withstand.
With the development of Ultra-High Performance Concrete (UHPC), construction experts have access to even higher psi’s. Ultra-High Performance Concrete measures many times the regular strength and can reach up to 17,000 to 22,000 pounds per square inch. The resilience of this concrete, for example, is such that complex projects can be built without using steel reinforcements.
Trust the Construction Experts to Use the Right Materials
Constructors, Inc has been in the construction business for generations. Throughout the years, we have been witness to the great strength of concrete. From building roads and highways, driveways, and large structures, concrete has long been part of the construction business.
Looking for construction experts for your project? Call Constructors, Inc today and learn more about our experience in building New Mexico. We can help your project get off the ground too!