What equation provides information on crown or tangent runout, Lt?

• A. Eq. 3-22
• B. Eq. 3-24
• C. Eq. 3-26
• D. Eq. 3-28

Answer: (B)

The equation that provides information on crown or tangent runout, often denoted as Lt, is specifically formulated to assess how the roadway or pavement surface conforms to the desired alignment and profile. This information is crucial in transportation engineering, particularly in road design and maintenance, where ensuring a smooth and safe riding surface is essential.

In the context of road design, crown refers to the slope or curvature of a road that helps with drainage, while tangent runout relates to how the road transitions from straight to a curve. The specific equation you chose can include variables that represent different aspects such as radius of curvature, design speed, or other geometric parameters pertinent to road design.

The other equations listed may address different aspects of road geometry or pavement analysis, such as superelevation, cross slope, or vertical curve calculations, but they do not pertain specifically to the measurement or analysis of crown or tangent runout. The confirmation that option B is correct demonstrates an understanding of how essential these calculations are for maintaining appropriate road conditions, which directly influence vehicle dynamics and driver safety.