What is the advantage of using a Shelby tube?

• A. A) It allows for easy mixing of soil samples
• B. B) It minimizes soil disturbance
• C. C) It is cost-effective
• D. D) It can penetrate rock layers

Answer: (B)

Using a Shelby tube offers the significant advantage of minimizing soil disturbance during sampling. This is crucial in geotechnical investigations because obtaining an undisturbed sample helps preserve the natural structure and moisture content of the soil, allowing for more accurate analysis of its engineering properties. The Shelby tube is specifically designed to collect cylindrical soil samples, with a thin wall that reduces the disturbance caused by the sampling process. The ability to maintain the in-situ conditions of the soil makes these samples ideal for laboratory testing, which can lead to better insights into the soil's behavior under load and its suitability for construction projects.

Other options might suggest benefits like cost-effectiveness or penetration capabilities, but those elements do not directly relate to the primary function of the Shelby tube in preserving soil integrity during sampling.