Abstract:
Construction productivity, which is measured by output per unit of resource, plays a key roll
in the success of a construction project. High productivity leads to a lower cost to carryout a
task or operation (YUN-YI SU; 2010). However, analyzing construction productivity is a
challenging task because of the nature of construction field condition which contains
complex resource flow that lacks the organized production lines of a manufacturing facility
in a controlled and weather protected environment. Moreover, the wide variety of site
condition has made the analysis difficult. Estimating actual output of resources from daily
execution data can provide construction engineer with insightful information for
productivity of resources on site. Estimating actual productivity is a key element in
estimating the time and cost required to complete construction operations (Oglesby et al.
2002).
The primary purpose of this study is to conduct site observation to estimate actual out put of
equipments and develop optimal crew formation for sub-base activity in road construction
projects. This case study is conducted on shashemene-Wondogenet-Gemeto road up grading
projects which is one of the Ethiopian Road Authority projects. The study is conducted on
the road section from Km22+300.00 – Km23+300 for a total of 1km. Data is collected for
actual out of equipments utilized in the operation. The actual output of equipments on site is
used in composition the resources for optimal crew formation .The equipments utilized in
this activity includes dozer, loader, grader, dump truck, water truck and pump. The day to
day activities and the output of each equipment is registered by data collector and checked
by the immediate foreman and site engineer. Data analysis is made for composition of
equipments to eliminate idle hour or redundancy of equipments. Based on the analysis
optimal and improved combination of these equipments is made and their combined out put
is determined which is the standard crew output of sub-base activity.
According to the study and from the result of the analysis, the optimal crew formation for
1km of sub-base activity is one dozer, one loader, one grader, one loader five dump truck,
one water truck and one pump. The combined out of the crew is 2,750m3
.
