COMPARATIVE ANALYSIS OF MECHANICAL AND MANUAL MODES OF TRAFFIC SURVEY FOR TRAFFIC LOAD DETERMINATION

  • KO Kusimo
  • FO Okafor
Keywords: Volume/Flow, Rate of Flow, Average Daily Traffic (ADT), Annual Average Daily Traffic (AADT), Equivalent Single Axle Load (ESAL).

Abstract

Traffic survey was carried out to obtain data that are necessary for traffic study and evaluation. One of the most important characteristics of a traffic stream is its volume which can be defined as the number of vehicles passing through a section of a road per unit time.  The road project which is approximately 75 km in length consists of a number of traversed roads, but the traffic study is focused only on the 6 major intersections. The surveys of traffic were conducted using volume count from 7am to 7pm each day because working at night is very unsafe in this area, by using an automatic traffic recorder (Trax 1 Plus) and road tube installation for collecting accurate data with manual counting for comparison. This study aims to analyze the current road traffic data collection methods - comparing both mechanical and manual mode of Traffic Survey simulation - in terms of capabilities and limitations on Nigeria roads using Ogoja (Mbok) Junction and Mfum road in Cross River State as a case study. The tendency of the mechanical counting machine to withstand nonstop24hrs-continuous counting was noted during the exercise compared to manual counting, since security at night cannot be predicted on manual.  The design equivalent standard axle load (ESAL) generated from the result shows that Ikom-Cameroon Junction has the highest value with a difference of (0.999x10^6 ) between the mechanical and manual, this value shows  a downward effect using manual data for the pavement structural thickness evaluation, this can further degenerate to the structural failure at the earlier stage, tensional fatigue, cracks etc. However, traffic study for the period 2015 to 2035 was considered in the analysis, the equivalent standard axle load (ESAL) generated along the section of the corridor and the pavement thickness shows that automatic counter machine is more accurate than the manual. Nonetheless the mechanical counter is more advantageous compared to the manual counter to this reasons the mechanical counter should therefore be employed during the raw data traffic survey. Manual on the other hand less useful for traffic survey in predicting the feature traffic analysis.

 

http://dx.doi.org/10.4314/njt.v35i2.1

Published
2016-03-30
Section
Building, Civil & Geotechical Engineering

Journal Identifiers


eISSN: 2467-8821
print ISSN: 0331-8443