NICET Construction Materials Testing Soils Level I Practice Test

The performance of a road can greatly be influenced by its bearing capacity, stability, and resistance to deformation under load, all of which are closely linked to soil shear strength. Shear strength refers to the soil's ability to resist sliding along internal surfaces, which is crucial when the soil supports the weight of vehicles and traffic loads.

When the shear strength is inadequate, the road can experience problems such as rutting, cracking, and overall structural failure. Engineers assess the shear strength of soil during the design phase to ensure that it can support anticipated loads throughout its lifespan. Factors such as moisture content, density, and soil composition influence shear strength, making it a critical property in road performance evaluations.

In contrast, while soil density and moisture content are important, they contribute to shear strength rather than being direct performance indicators on their own. Soil color, on the other hand, does not impact the engineering properties necessary for road performance. Thus, understanding and managing soil shear strength is fundamental in the construction and maintenance of effective roadways.