Ready Mix Concrete Tips: Ready Mix Ordering Tips
Are you ready to order ready mix concrete? If you think so, then think twice. You could be ordering the wrong mix design, reducing your revenues or offering a product that is not the ideal concrete mix design. Here we have prepared a list of productive tips that you should know before ordering ready mix concrete.
Ready Mix Concrete Tips
Are you ready to order ready mix concrete? If you think so, then think twice. You could be ordering the wrong mix design, reducing your revenues or offering a product that is not the ideal concrete mix design. Here we have prepared a list of productive tips that you should know before ordering ready mix concrete.
Ready Mix Concrete Strength
One of the most important factors before ordering ready mix concrete is knowing what will be the required compressive strength. Typically reinforced concrete ranging between 3,500 to 4,000 psi is used on footing and slabs on grade; between 3,500 to 5,000 psi on suspended slabs, beams and girders; walls and columns normally required between 3,000 to 5,000 psi. When non-reinforced concrete is used then different strengths will be required. If you are using it on footings and walls a concrete strength of 2,500 psi could be enough, and between 4,000 to 5,000 for pavements. Outdoor concrete used on home improvements should be ordered with a strength ranging between 3,500 to 4,500 psi.
Ready Mix Concrete Aggregates
The maximum coarse aggregate must also be specified when ordering ready mix concrete. If you use larger coarse aggregate in a cross section where the steel ratio is high, then you should be creating a bug hole problem. The maximum size coarse aggregate ordered must be determined by the American Concrete Institute Standard (ACI) and depends on the spacing of reinforcing steel, inside form dimensions and available aggregates.
Maximum aggregate shall not exceed 1/5 the narrowest inside form dimension and shall not be greater than ¾ the spacing between re-bars.
Ready Mix Concrete Slump
Determine the best slump.
Slump is the consistency of the concrete when it’s being placed. Slump shall be specified low although it will vary depending on reinforcement spacing, formwork type and the slope or the place where it will be placed. Slumps are also determined by ACI standards although we can recommend the following:
Reinforced foundation wall and footings: 2 minimum 5 maximum
Footings, caissons: 1 minimum, 4 maximum
Slabs, beams, building columns and reinforced walls: 3 minimum and 6 maximum
Pavements: 2 minimum and 3 maximum
Heavy Mass Concrete: 1 minimum and 3 maximum
Ordering Ready Mix Concrete
Ready Mixed concrete is normally ordered by cubic yards. The typical truck could deliver between 9 to 11 cubic yards maximum capacity although less amounts could also be ordered. The amount of concrete being ordered will also depend on the place where it will be placed, and the form used. Always allow for some wasted concrete that normally will vary between 5 to 10 percent additional concrete. For a rectangular placing area multiply length times wide times thickness, in feet, and divide it by 27.
That amount will be the necessary cubic yards of concrete needed. When using a cylindrical shape, such as a column, measure its height multiply by 3.14, then by the square of the cylindrical radius, and then divide it by 27.
Other Important Ready Mixed ConcreteTips
Remember to also know if you are using an admixture, specified how far is the job site from the batch plant, the arrival time of the concrete that you are requesting, the desire spacing of concrete trucks, specify if you need any fiber or plasticizer, how the concrete is going to be placed (tailgate, pump, wheelbarrow, etc.), air or non-air mix, total amount of ready mix ordered, contact person, concrete mix id number, and the purpose of the concrete. Finally inform the concrete batch plant the conditions of where the ready mix will be placed (slope, incline roof, limited space, basement, roof, or any relevant information that could affect the progress of the pour.
Source: construction.about.com
