Example number two. You are a contractor, and you have been asked to calculate how much concrete will be required for 25 concrete footings for a 48-story skyscraper, covering a footprint of 200 x 400 feet. The footings will be 2 feet in length, 2 feet in width, and 12 inches deep. Additionally, there's been a foundation well placed that is 8 inches thick and will be 2 feet tall, placed continuously on each pad, along the perimeter of the building. And number 6 rebar will be placed vertically, within the foundation wall, 48 inches on center. Finally, 4 number 4 rebars will be placed into each footing. So how do we begin? First, we want to quantify the cubic footage of the footings. That calculation is performed, By measuring out the dimensions, 2 x 2 x 1, for a total of 4 cubic feet per footing. Next, we need to multiply that by the total quantity of the footings, which brings us to a total of 100 feet cubed. And then finally, we want to solve for a cubic dimension of the foundation wall. So we know that it is going to be placed on the footings around the perimeter of the building, and we know that it is has a 200 x 400 dimension. Therefore, the perimeter would be 1,200 feet for the foundation wall. So we would multiply 2 feet in height, times 0.67, which is inches converted into feet, for 8 inches thick. And the perimeter length, which is 1,200, for a grand total of 1,608 cubic feet of concrete. So, it is very important to remember to convert from cubic footage into cubic yardage. Therefore, we will take the total quantity of bulk concrete for the footings, which is 100 feet cubed, multiplied by the bulk concrete for, sorry, added to the bulk concrete for the foundation wall, which is 1,608. We take that factor and divide it by 27, for a grand total of 63.26 cubic yards. Next, we want to quantify the length, quantities, and weights of the rebar. So we know from our example, that 4 number 4 bars would be placed per footing, for a grand total of 100 total number 4 rebar. We know that the length of the footings is 2 by 2. So we can understand that the length of the rebar will be 2 linear feet, multiplied by 100 total rebar, for a grand total of 200 linear feet of number 4 rebar. Finally using the ASTM model which we described earlier, you will multiply the total rebar for the footings, by 0.668 pounds, for a grand total of 133.6 pounds of number 4 rebar. Onto the foundation wall, we know that there is 1,200 linear feet of foundation wall. We also know that converting for inches of the foundation wall, will bring us to a total of 14,400 inches. We need to divide 14,400 into 48, because that is the on center placement of the number 6 rebar. And that comes up with a number of, 300 total number 6 rebar. Secondly, we need to find out what the total length is going to be with the rebar. We know that the foundation wall is 2 feet high, and that the rebar is placed vertically. Therefore we will multiply 300 rebar, by 2 linear feet, for a total of 600 total linear feet of number 6 rebar. Finally, the last calculation using our ASTM model, will be to calculate the weight of the total reinforcement bar. That is performed by multiplying 600 by 1.502, for a grand total of 901.2 pounds of number 6 rebar. Finally, we want to understand what the surface area of the formwork is. So there are two elements in this example. One being the footings, which are going to be poured in place. We know that they have a length of 2 feet on each side, and 12 inches, or 1 foot, of height. So we multiply 2 times 1 times 25, which is the total number of footings, for a grand total of 50 square feet. Finally, for the foundation wall, we understand that there are 200 linear feet, Times 2 feet of height, multiplied by 2 sides of the foundation wall. And then similarly for the length, you have 400 multiplied by 2 feet in height, times 2, for a grand total of 2,400 square feet of formwork. Okay, so in our second example, you are playing the role of a contractor and you have been asked to calculate how much concrete will be required for 25 concrete footings, for a brand new, 48-story skyscraper. Which will be covering a footprint of 200, By 400 feet. These footings will be 2 foot by 2 foot by 12 inches deep, and will be placed along the perimeter of the building. Additionally, there's going to be a foundation wall that is 8 inches thick, And we'll have number 6 rebar placed vertically, 48 inches on center. Finally, in each one of these footings, 4 number 4 rebar will be places. So the first Item that we want to quantify is the cubic footage of each footing. So we know that the footings are 2 feet, by 2 feet, by 1 foot, or 12 inches deep. Which brings us to total of 4 cubic feet per footing. We also understand that there are 25 total footings for the entire project, therefore the calculation would then be 4 x 25, for a total amount of 100 cubic feet of concrete from the footings. Secondly, we want to solve for a dimension for the foundation wall. So we know that the foundation wall is 200 by 400 in terms of length and width. We must solve for the perimeter, so that would be 200 + 200 + 400 + 400, Which brings you to a total of 1,200 linear feet of foundation wall. We also know that the foundation wall is 2 feet high. So you multiply 2 x 1,200, and then you need to calculate for the thickness of the foundation wall in terms of feet. 8 divided by 12, as we discussed earlier, is 0.67. Therefore, you must multiply 2 x 1200 x 0.67, for a total of 1,608 cubic feet. Okay finally, you must remember to calculate for cubic yardage from cubic feet. So we know we have 100 cubic feet of footings, 1,608 cubic feet of foundation wall, which brings us to a grand total of 1,708 cubic feet of bulk concrete. We divide that number by 27, To understand that there is a total of 63.26 cubic yards of concrete for the project.