Which soil type is most suitable for use as an embankment shell?

Which soil type is most suitable for use as an embankment shell?

• A. GW
• B. GC
• C. SM
• D. OL

Answer: (A)

The most suitable soil type for use as an embankment shell is well-graded gravel, commonly classified as GW. This soil type has distinct characteristics that make it ideal for the outer layer of an embankment. Well-graded gravel possesses good drainage properties, which helps in preventing water accumulation within the embankment. Proper drainage is essential in maintaining the stability and integrity of the embankment, as excess water can lead to soil erosion, increased pore pressures, and ultimately, failure of the structure. The larger particles in well-graded gravel create voids that allow for effective water flow, significantly minimizing the risks related to infiltrating water. In addition to drainage, GW offers excellent shear strength and stability when compacted. The variety of particle sizes within the gravel helps produce a dense structure, contributing to the embankment shell's stability under load. The high bearing capacity associated with well-graded soils makes them an ideal choice for supporting roads, railways, and other infrastructures often constructed atop embankments. While other soil types listed may have certain advantages in specific contexts, they do not provide the combination of drainage, stability, and load-bearing capacity that GW offers, making it the most suitable option for an embankment shell.

The most suitable soil type for use as an embankment shell is well-graded gravel, commonly classified as GW. This soil type has distinct characteristics that make it ideal for the outer layer of an embankment.

Well-graded gravel possesses good drainage properties, which helps in preventing water accumulation within the embankment. Proper drainage is essential in maintaining the stability and integrity of the embankment, as excess water can lead to soil erosion, increased pore pressures, and ultimately, failure of the structure. The larger particles in well-graded gravel create voids that allow for effective water flow, significantly minimizing the risks related to infiltrating water.

In addition to drainage, GW offers excellent shear strength and stability when compacted. The variety of particle sizes within the gravel helps produce a dense structure, contributing to the embankment shell's stability under load. The high bearing capacity associated with well-graded soils makes them an ideal choice for supporting roads, railways, and other infrastructures often constructed atop embankments.

While other soil types listed may have certain advantages in specific contexts, they do not provide the combination of drainage, stability, and load-bearing capacity that GW offers, making it the most suitable option for an embankment shell.