Which instrument is used to evaluate soil strength by recording blows at fixed penetration increments?

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Multiple Choice

Which instrument is used to evaluate soil strength by recording blows at fixed penetration increments?

Dynamic evaluation of soil strength is done by driving a cone into the soil with a hammer and recording how many blows are needed to advance it a fixed distance. The Dynamic Cone Penetrometer uses a weighted hammer dropped from a standard height to push a conical tip into the ground, and you count the blows required for each 10 cm of penetration. Areas that require more blows for each increment indicate stiffer, stronger soil, while fewer blows point to weaker material. This method gives a quick field estimate of bearing strength and stiffness, which is especially useful for subgrade and pavement design in soft to moderately stiff soils. Other instruments measure strength in different ways. The Standard Penetration Test records blows needed to drive a sampler a fixed distance (but the test continues until a larger penetration, not in uniform 10 cm increments with a simple blow count per increment). The Cone Penetrometer Load Test applies a static load rather than dynamic blows. The Static Penetrometer Test uses a static load as well, not a dynamic hammer impact.

Dynamic evaluation of soil strength is done by driving a cone into the soil with a hammer and recording how many blows are needed to advance it a fixed distance. The Dynamic Cone Penetrometer uses a weighted hammer dropped from a standard height to push a conical tip into the ground, and you count the blows required for each 10 cm of penetration. Areas that require more blows for each increment indicate stiffer, stronger soil, while fewer blows point to weaker material. This method gives a quick field estimate of bearing strength and stiffness, which is especially useful for subgrade and pavement design in soft to moderately stiff soils.

Other instruments measure strength in different ways. The Standard Penetration Test records blows needed to drive a sampler a fixed distance (but the test continues until a larger penetration, not in uniform 10 cm increments with a simple blow count per increment). The Cone Penetrometer Load Test applies a static load rather than dynamic blows. The Static Penetrometer Test uses a static load as well, not a dynamic hammer impact.

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