Which technique involves measuring tip resistance directly in soil?

• A. Standard penetration test
• B. Cone penetrometer
• C. Vane shear test
• D. Excavation sample

Answer: (B)

The technique that involves measuring tip resistance directly in soil is the cone penetrometer. This method uses a conical tip that is pushed into the ground, and it allows for the direct measurement of the resistance encountered by the tip as it penetrates the soil. This resistance data provides valuable information about the soil's strength and stratification.

The cone penetrometer test is particularly useful in determining the consistency and load-bearing capacity of soils, which is critical for geotechnical engineering projects. As the tip is pushed into the ground, the resistance profiles can be used to infer soil properties such as shear strength and effective stress, making it an efficient in-situ testing method.

In contrast, the standard penetration test primarily involves dropping a weighted hammer onto a hollow sampling tube to obtain soil samples and measure how many blows are required to achieve a certain penetration depth. While it offers some insights into soil characteristics, it does not provide a direct measurement of tip resistance like the cone penetrometer does.

The vane shear test is designed to measure the shear strength of cohesive soils using a vane apparatus, and while it offers important data, it does not focus on tip resistance in the same way. Excavation sampling involves physically removing soil samples from a site for analysis, which