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CDOT Roadway Design Guide 2018

Issued on October 25, 2018. Includes 2018 revisions to the 2005 CDOT Roadway Design Guide.
Design Bulletin 2018-07 - 2018 CDOT Roadway Design Guide (RDG)
Design Bulletin for the issuance of the 2018 CDOT Roadway Design Guide.
2018 revisions to the 2005 CDOT Roadway Design Guide
Yellow highlights are content changes with green highlights being reference updates.
File CDOT Roadway Design Guide 2018 (Complete Guide)
File Cover
File object code Introduction
File C source code Table of Contents
File Chapter 1 - Functional and Contextual Highway Classifications
To differentiate between the types of highways, functional and contextual classifications have been developed so that engineers, administrators, and the general public can communicate about highways.
File Chapter 2 - Design Controls and Criteria
Chapter 2 discusses characteristics of vehicles, pedestrians and traffic that act as criteria for the optimization or improvement in design of the various highway and street functional classes.
File Chapter 3 - Elements of Design
There are elements of design common to all classes of highways and streets, which include sight distance, superelevation, traveled way widening, grades, and horizontal and vertical alignments.
File Chapter 4 - Cross Section Elements
Types of Cross Section Elements
File Chapter 5 - Local Roads and Streets
Local roads or residential streets primarily serves as access to a farm, residence, business, or other abutting property. The through traffic is local in nature and extent rather than regional, intrastate, or interstate.
File Chapter 6 - Collector Roads and Streets
This chapter is subdivided into rural collectors and urban collectors. Consult Chapter 3 and Chapter 4 of this Guide for details on the basic design elements applicable to these classification of roadways.
File Chapter 7 - Rural and Urban Arterials
Rural arterials range from two-lane roadways to multilane, divided controlled-access arterials. Urban arterials carry large traffic volumes within and through urban areas. Their design varies from freeways with fully controlled access to two-lane streets. Consult Chapter 3 and Chapter 4 for details on the basic design elements applicable to these classification of roadways.
File Chapter 8 - Freeways
The highest type of arterial highway is the freeway, which is defined as an arterial highway with full control of access and no at grade crossings or connections. This chapter identifies the various types of freeways, emphasizes selected features, and discusses other design details unique to these freeway types. Consult Chapters 3 and 4 for details on the basic design elements applicable to this classification of roadway.
File Chapter 9 - Intersections
An intersection is defined as the general area where two or more highways join or cross, including the roadway and roadside facilities for traffic movements within it. These movements may be handled by various means, such as signals, signing, and channelization, depending on the type of intersection.
File Chapter 10 - Grade Separations and Interchanges
An interchange is a system of interconnecting roadways in conjunction with one or more grade separations that provide for the movement of traffic between two or more roadways or highways on different levels.
File Chapter 11 - Access Control and Access Management
Access management is the planned and regulated interaction between the roadway network and property access.
File Chapter 12 - Accessible Pedestrian Design
This Chapter provides guidance and direction regarding the requirements for the design of accessible pedestrian facilities so they are accessible to all potential users in all roadway environments.
File Chapter 13 - Alternate Standards (Low Volume Roads)
A low-volume local road has an average daily traffic volume of 400 vehicles per day maximum.
Chapter 14 - Bicycle and Pedestrian Facilities
Multimodal transportation is a key element of CDOT’s mission in providing improvements to the statewide transportation system. CDOT has adopted a Policy Directive and a Procedural Directive to improve the accommodation of bicycles and pedestrians in CDOT programs. (Unchanged from the 2005 Guide.)
File Chapter 15 - Bridge
This chapter addresses the basic issues the roadway designer must consider when designing a roadway project that includes major or minor structures. The Staff Bridge Branch will play an active and early role in the development of the project- specific activities related to highway structures.
File Chapter 16 - Construction Specifications
This chapter defines Standard Specifications and Special Provisions. It provides details on the format and guidelines for writing Special Provisions, and describes the approval process for both Standard and Project Special Provisions.
Chapter 18 - Noise Guide
This chapter is intended to help designers identify issues related to highway traffic noise, understand the applicable federal and state regulations and guidelines, analyze traffic noise for specific projects, and select and implement noise mitigation measures. (Unchanged from the 2005 Guide.)
File Chapter 19 - Roundabouts
A roundabout is a form of a circular intersection in which traffic travels counterclockwise around a central island where entering traffic must yield to circulating traffic.
File Chapter 20 - Safety and Traffic Engineering
The mission of CDOT's Traffic and Safety Engineering Branch is to reduce the frequency and severity of motor vehicle crashes which have a comprehensive and economic cost. This chapter addresses most, but not all, important design issues related to providing a safer transportation system.
File Index

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