How A Concrete Compression Strength Test Works
As we noted in our last post about precast concrete strength, curing it on site in the factory is the key to quality control. And in that quality control, we’re looking to preserve the material’s strength and longevity above all else. The compressive strength of the concrete is a result of how permeable it is, and the lower the better.
We’re after dense concrete, so we add cement, which fills up any tiny open areas where water or other fluids could go. How do we know for sure that our concrete has reached peak power? We give it a compression strength test. Compressive strength is measured in PSI (pounds per square inch), a number we arrive at by first molding the concrete into either a cube or a cylinder. Once we fill our mold, we keep that concrete form at a strictly controlled temperature and humidity, demolding it just before the test. Tests are often performed at 1, 3, 7, 14 and 28 days, at which point the mold goes into a Compression Testing Machine. The machine applies an unwavering level of stress to the cube or cylinder. When the test is complete, we take stock of cracks and expansion and match it against existing data to configure the PSI.
Precast products fall within the 4,000 to the 5,000 PSI range, making them an incredibly durable solution for builders, designers, architects, and urban planners.