Any good contractor knows that you do not build on a weak foundation. The metric in which concrete strength is measured is called an MPa. This unit of force is used to calculate the strength of concrete. The amount of cement added to the concrete mixture determines the MPa strength. Air-entrainment is also part of the process in which a percentage of air is incorporated to increase durability. Depending on your project’s requirements, the batch is weighed, measured, and tested for resilience by a technical service coordinator.
Measurement of force
Strength capacity, a pascal is one newton of force per square meter. A megapascal is one million newtons per square meter. A quality control operator measures the compressive strength of a cured mortar cube which is measured by executing the maximum weight to break the cube. That amount is then divided by the cross-sectional area of the cube. Temperature and moisture can affect concrete strength but providing structural additions such as mesh, rods, and wires can improve the strength quality.
How to determine which strength is needed per project
Standard and Residential – 32 MPA-2 0.45 W/C
Common usage- Curb and sidewalk, walkways, industrial floors, residential/commercial garage floors, fence posts, patios, staircase, and decks.
8.3 MPA LDF w/ Peastone Air
Common usage- communication utility backfill (conduit mix), trench backfill, utility cut backfill, fill voids, fill voids in tunnels, backfill in congested areas and pool infill.
0.4 MPA super flowable fill
Common usage- trench backfill, utility cut backfills, fill void, fill void in tunnels, backfill in congested areas and pool infill.
0.4/0.7 MPA LDF w/20MM AGG
Common usage- trench backfill, utility cut backfills, fill voids and backfill in congested areas.
Testing explained
We at SMR use multiple tests to determine consistency, compressive strength and elastic properties of the concrete material.
Common tests used within the concrete field include: a slump test, rebound test, penetration test, testing cubes, vibration test and the pull-out test.
A slump test is when concrete is poured into a cone “like” form, tapping and pouring until it is leveled off. Once the cone is removed, the consistency of the concreate should remain the same, between 50-75 mm.
A rebound test is performed by using a rebound hammer, measuring stress waves and impact. Once the test has been administered the rebound numbers are then recorded.
At SMR we pride ourselves on quality, accuracy, and consistency. Preforming these test methods allow our team to measure concrete samples, further ensuring quality control and enhancing performance.
Other common testing methods
A penetration – a steel rod is propelled into a sample; the depth of the penetration will be the determining factor for its strength.
Testing cubes are used by taking a sample of concrete then applying forced pressure to break the cube.
Vibration test, measuring vibration waves that move through concrete.
Pull-out test- steel rods are cast within a concrete sample then purposely removed with aggressive force.
Knowledge is power, however there is no need to remember high school physics. We here at SMR take the responsibility and all the calculations off your mind. We ensure thorough efficacy and accuracy to secure your project with a solid foundation. Use Stouffville Mobile Redimix for all your redimix concrete needs.