Question

Assume you have 0.5 m3 of soil with a porosity of 40% and an oven-dry weight of 700 kg. Calculate the bulk density. Next, assume that I drive over the soil with heavy equipment, compact the soil, and reduce the total porosity to 20%. Calculate the bulk density after compaction.

Answer 1

Answer:

bulk density = 1400 kg/m³

bulk density  after compaction = 1750 kg/m³

Explanation:

given data

volume = 0.5 m³

porosity = 40%

oven-dry weight = 700 kg

reduce the total porosity = 20%

to find out

bulk density and bulk density after compaction

solution

we know bulk density formula that is

bulk density = $\frac{weight}{volume}$          ...............................1

put here value we get

bulk density = $\frac{700}{0.5}$    

bulk density = 1400 kg/m³

and

if porosity decrease 20 % that mean volume change

so total volume = 0.5 $\frac{80}{100}$

total volume = 0.4 m³

so bulk density after compaction is from equation 1  

bulk density =  $\frac{700}{0.4}$  

bulk density  after compaction = 1750 kg/m³