During a sampling operation, the drive sampler is advanced 600 mm and the length of the sample recovered is 525 mm. What is the recovery ratio of the sample?
0.875
Sampling Recovery Ratio Explained
In sampling operations, the term recovery ratio is used to measure how much of the material was successfully collected compared to the distance the sampler was driven or pushed into the ground. It essentially tells us the efficiency of the sampling process.
Understanding the Drive Sampler Operation
The question describes a scenario using a drive sampler, a common tool in geotechnical and environmental site investigations. The sampler is advanced (driven) into the soil for a specific distance, and then the length of the soil sample successfully collected inside the sampler is measured.
Calculating the Recovery Ratio
To calculate the recovery ratio, we use a straightforward formula:
$$ \text{Recovery Ratio} = \frac{\text{Length of Sample Recovered}}{\text{Length Drive Sampler Advanced}} $$
Applying the Formula to the Problem
Let's apply this formula using the values provided in the question:
- Length the drive sampler was advanced = 600 mm
- Length of the sample recovered = 525 mm
Now, substitute these values into the formula:
$$ \text{Recovery Ratio} = \frac{525 \text{ mm}}{600 \text{ mm}} $$
Step-by-Step Calculation
To find the numerical value, we perform the division:
- Divide the recovered length by the advanced length: $525 \div 600$.
- Simplify the fraction or perform the division directly.
- $525 \div 600 = 0.875$
Therefore, the recovery ratio of the sample is 0.875.
Interpreting the Recovery Ratio
A recovery ratio of 0.875 means that 87.5% of the distance the sampler was driven resulted in a successful sample recovery. This indicates a good recovery efficiency for the sampling operation.
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