100 lb of loose gravel can fill a 1-ft^3 box. Its specific gravity is 2.68. What is the dry rodded weight?
"The dry rodded unit weight of aggregate is determined by compacting dry aggregate into a container of a known specific volume according to standard procedures."
It is not known if the gravel was compacted as per standards into the 1 ft³ container. If it was, the dry rodded unit weight is 100 lb/ft³. If it was not, the dry rodded weight is likely to be slightly higher, but in any case, not exceeding 62.4*2.68=167 lb/ft³.
The specific gravity refers to the specific gravity of the material, i.e. a solid chunk of the material, without voids.
Thanks so much, I was confused and then I used specific gravity formula and i got 167 lb.
You're very welcome!
To find the dry rodded weight of the gravel, we need to understand what specific gravity means and how it relates to weight.
Specific gravity is a ratio that compares the density of a substance to the density of a reference substance, usually water. In this case, the specific gravity of the gravel is given as 2.68.
Now, let's break down the problem step by step:
Step 1: Determine the density of water
The density of water is commonly known, which is approximately 62.4 lb/ft^3. This value will be used as the reference density for specific gravity calculations.
Step 2: Calculate the density of the loose gravel
Since we know that 100 lb of loose gravel can fill a 1-ft^3 box, the density of the gravel can be calculated by dividing the weight by the volume:
Density = 100 lb / 1 ft^3 = 100 lb/ft^3
Step 3: Calculate the dry rodded weight
The dry rodded weight refers to the weight of the gravel as if it were compacted and void-free. It is calculated by multiplying the density of the gravel by its specific gravity:
Dry Rodded Weight = Density of gravel x Specific Gravity
Dry Rodded Weight = 100 lb/ft^3 x 2.68
Now we can calculate the dry rodded weight of the gravel:
Dry Rodded Weight = 100 lb/ft^3 x 2.68 = 268 lb/ft^3
Therefore, the dry rodded weight of the gravel is 268 lb/ft^3.