What is Concrete?

Concrete is everywhere, but it’s often misunderstood. Sidewalks, slabs, curbs, ramps, foundations, loading docks, and plazas may look simple, but concrete is a carefully engineered material. When done right, it’s strong, durable, and precise. When done wrong, it cracks, settles, and causes long-term problems.

Let’s walk through what concrete actually is, how it works, and why the details matter.

The Basics

Concrete is a man-made composite material created by mixing four primary ingredients:

• Cement – the binding agent

• Aggregates – sand and stone that provide strength and structure

• Water – activates the cement and allows the mix to harden

• Air (intentionally or unintentionally added) – affects durability and workability

Cement is not concrete. Cement is one ingredient. When water is added, a chemical reaction called hydration begins. This reaction causes the cement to bind the aggregates together into a solid mass.

Once concrete hardens, it doesn’t “dry” in the traditional sense. It cures as the chemical reaction continues over time.

Why Concrete Is Strong (and Why It Cracks)

Concrete is extremely strong in compression. That’s why it’s ideal for surfaces and structures that carry weight.

However, concrete is relatively weak in tension (pulling forces). Temperature changes, ground movement, and shrinkage during curing all create stress. That stress has to go somewhere.

Cracks are not always a sign of failure. In many cases, cracking is expected and managed through:

• Control joints

• Expansion joints

• Reinforcement

The goal is not to eliminate cracking entirely, but to control where and how it happens.

Reinforcement Matters

Concrete on its own can only do so much. Reinforcement is used to improve performance and longevity.

Common reinforcement methods include:

• Steel rebar

• Wire mesh

• Fiber reinforcement (synthetic or steel fibers mixed into the concrete)

Different applications call for different approaches. A sidewalk, a slab-on-grade, and a loading dock may all use concrete, but the reinforcement strategy will vary based on load, use, and soil conditions.

There is no single “best” reinforcement method for every project.

Concrete Is All About Preparation

Most concrete problems don’t start in the concrete itself. They start below it.

Subgrade preparation is critical and may involve:

• Excavation

• Compaction

• Gravel base installation

• Drainage considerations

If the base moves, the concrete will move. Concrete does not flex the way asphalt does. It transfers stress instead of absorbing it. That’s why poor preparation often shows up later as cracking, settling, or uneven slabs.

Finishes, Slopes, and Details

Concrete isn’t just structural. It’s also functional and visual.

Finish options can include:

• Broom finish for traction

• Smooth or steel-troweled finishes

• Decorative or architectural finishes

Slope matters just as much as appearance. Concrete must be pitched correctly to manage water and prevent pooling. Small errors during placement can lead to long-term drainage issues.

Details like edge work, joint spacing, and curing methods all play a role in how concrete performs over time.

Concrete Is Durable, Not Indestructible

Concrete is long-lasting, but it is not maintenance-free.

Factors that affect longevity include:

• Freeze-thaw cycles

• Deicing salts

• Water infiltration

• Load stress over time

Proper design, placement, and curing dramatically extend concrete’s lifespan. Poor decisions early on are difficult and expensive to correct later.

The Big Picture

Concrete is a precise material. It rewards planning, patience, and attention to detail. When designed correctly for its purpose and installed properly, it can perform for decades. When rushed or treated as “just a pour,” problems tend to show up sooner than expected.

Understanding concrete means understanding that strength comes from preparation, design, and execution working together.

If you have any questions about concrete work, design options, or what approach may make sense for your property, feel free to reach out to us at Atlantic Mason. We’re always happy to walk through the details.

Serving NY, NJ, and CT, Atlantic Mason provides asphalt paving, concrete flatwork, and masonry services for both residential and commercial properties. From driveways and walkways to parking lots, curbs, and site work, we help clients make informed decisions about repairs, maintenance, and upgrades