Civil Engineering Professional Engineer Practice Exam 2025 – All-in-One Comprehensive Guide to Exam Success!

A retaining wall is primarily designed to prevent soil erosion and collapse by holding back soil and other materials at various angles. This is critical in situations where there is a change in elevation, such as on hillsides or in landscaping where different levels need to be maintained. The wall provides stability and support to the ground behind it, reducing the risk of landslides or soil movement that can occur due to gravity or water flow. This is essential in civil engineering projects to ensure safety and longevity of structures built on or near sloped terrain.

The other choices, while they may relate to various aspects of civil engineering, do not directly pertain to the primary purpose of a retaining wall. Reinforcing concrete strength is a concern in many concrete structures but not a primary function of retaining walls. Similarly, controlling water runoff is typically managed through drainage systems rather than walls designed to hold back earth. Providing structural insulation does not align with the function of retaining walls, which focus more on the mechanical stability of materials rather than thermal properties.