Page 90 - HIGHWAY ENGINEERING LABORATORY_FLIP BUILDER

Page :
WORK INSTRUCTION
Edition :
Checking No.
SPOT SPEED STUDY
(Reference Standard:
CIVIL ENGINEERING AASHTO. 2001) Effective Date:

JKA/ DCC30112/ 2021 Amendment Date:

1.0 OBJECTIVE :

To determine and analyze the average speed of the roadway/highway

2.0 THEORY:

Prior to planning and designing a traffic system it is necessary to collect traffic data to
be analyzed, and studied in depth. Field surveys are needed to make a detailed plan.
The data collected will be sufficient to represent and actual situation on the

characteristics of traffic in the area. Information is often collected in the field by

3.0 EQUIPMENTS :

Radar guns top watch measuring tape flags, safety vest

4.0 LOCATION :: Make sure the location is away from the intersection

5.0 PROCEDURE (Radar gun method)

1. Select a suitable area at Politeknik Mukah. (Make sure the site chosen is not dangerous
and does not interfere with existing traffic)
2. For the purpose of this study, an observer is appointed to observe vehicle speeds using

radar gun. The radar gun send out a radio signal, then receive the same signal back as it
bounces off target object. However, due to a phenomenon called the Doppler Effect,
if the object is moving, the frequency of the radio waves is different when they come

back, and from that difference the radar gun can calculate the object’s speed.
3. Dothesefor100vehiclesorONEHOUR.Recordthedatainthetableasshownbelow.

Higway Engineering Laboratory page 76