CE 373 Pavement Design Spring 1999

Project 1: Traffic Data for Pavement Design

The purpose of this project is for you to learn the basic mechanism for estimating ESAL for design, to develop a fuller understanding of the concept ESAL (and its shortcomings) and to gain an appreciation for the difficulties involved in trying to get accurate traffic data.

The main task is to estimate the traffic parameter needed for the design of a highway pavement using the AASHTO method of design. The pavement in question is on a new highway connector between Bolton and Windham, CT. This highway will roughly parallel the existing Rte. 6 at a distance of about two miles to the east. It will connect with I-684 at Bolton Notch and the Rt.6 freeway by-pass at Willimantic. The start date for construction is April 2000.

The maximum performance period for the pavement design is 15 years and the analysis period is 20 years. A handout containing recent traffic counts for roads in the vicinity of the project will be given in class.

Your report should include the following

  1. Estimate the ESAL: show all related calculations and clearly state the assumptions used to arriving at an answer.
  2. Souces of Error: Discuss the possible sources of errors in your estimation, the relative importance of each source of error and what data would be needed in order to improve the estimate.
  3. Sensitivity Analysis: Evaluate the effect on the design of over or under estimating the ESAL (use factors of 0.5 and 2.0, respectively). Based on this analysis, briefly discuss the importance in design of obtaining an accurate estimation of ESAL. Select parameters that are representative of a freeway class facility to do your sensitivity analysis.
  4. Shortcomings of ESAL Concept: Based on your knowledge of the ESAL concept briefly discuss its shortcomings from a theoretical point of view.

 

 

 

Traffic Data

Route 66

1990

1993

  

SW of Rte. 87

9670

8990

  

NE of Rte 87

10970

11220

  

Windham Town-line

9190

9400

  

E of US 6

8960

8104

  
       

US Route 6

1990

1992

1995

NW of Rte. 87

13500

14500

13700

E of Rte. 316

15000

14700

14160

Coventry Town-line

16500

16100

15400

Andover Town-line

11400

10400

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E-mail to Prof. Garrick

Date of last update - 17 Feb 1999