Question

1

a) What is the difference between an AADT and an ESA?

b) Why would you consider adopting a longer design life for a pavement?

c) What are three different methodologies for forecasting traffic volumes? What are their strength

Answer 1

Answer 1:

AADT is Annual Average Daily Traffic. AADT is the traffic of 24 hours for the year divided by 365.

ESA is equivalent Standard Axle which used to calculate load on road by each standard vehicle. ESA is calculate by considering mass of standard truck.

Answer 2:

Design life of pavement is consider longer because of the following reasons:

To provide high volume facility

to reduced delay to the passenger while passing during maintenance or reconstruction

To reduce life cycle cost of pavement

To reduce environmental impact

Answer 3:

Three different methodology to forecast traffic volume:

1)Qualititive Techniques: Here qualitative data which is collected by different traffic survey is used to forecast future traffic volume.

2) Time Series Analysis: In this methodology data from past and present year is collected and then growth of the traffic is measured. Based on this growth future traffic volume can be predicted.

3)Casual Methods: this mythology use relations like growth of the city, Increasing our decreasing use of public transportation, Increasing demand of four wheeler,etc. Based on these relationship forcasting of traffic volume is done.