Course NumberCE-03-909
PDH Hours3
Roadway Horizontal Alignments II

Roadway Horizontal Alignments II

Author: Gregory Taylor

Roadway horizontal alignments contain a series of horizontal tangents (straight roadway sections), circular curves, and spiral transitions. These show the proposed roadway in relation to the existing terrain and adjacent land conditions. Along with the vertical alignment (grades and vertical curves) and roadway cross-sections (lanes, shoulders, curbs, medians, roadside slopes, ditches, sidewalks), the horizontal alignment (tangents and curves) helps display a three-dimensional roadway layout.

In today’s environment, engineers must do more than apply design standards and criteria to ‘solve’ a problem. They need to understand how various roadway elements contribute to safety and facility operation, including the horizontal alignment.

This course is the second of two that focuses on the geometric design of horizontal alignments for modern roads and highways. Its contents are intended to serve as guidance and not as an absolute standard or rule. Upon course completion, you should be familiar with the general design of horizontal roadway alignments. The course objective is to give engineers and designers an in-depth look at the principles to be considered when designing horizontal alignments.
A Policy on Geometric Design of Highways and Streets (also known as the “Green Book”) published by the American Association of State Highway and Transportation Officials (AASHTO) is considered to be the primary guidance for U.S. roadway design. For this course, Chapter 3 (Section 3.3 Horizontal Alignment) will be used exclusively for fundamental roadway geometric design principles.

Once you complete your course review, you need to take a multiple-choice quiz consisting of fifteen (15) questions to earn 3 PDH credits

Learning Objectives

This course is intended to provide you with the following specific knowledge and skills

Design Considerations

  • Cross slopes
  • Radii
  • Grades

Traveled-way Widening

  • Design Methods

Sight Distance

  • Stopping
  • Decision
  • Passing
  • Intersection

General Design Controls
Coordination of Horizontal & Vertical Curves

Download the Course to review and begin earning your PDH credits.

We provide technical courses for PDH credits that meet Board requirements for Professional Engineers, Geologists and Land Surveyors. This courses is guaranteed to be accepted in AK, AL, AR, FL, GA, IA, IL, ID, IN, KS, KY, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, SC, SD, TN, TX, UT, VA, VT, WI, WV, and WY. Before purchasing this course, please confirm that your state Board is listed above.