Modeling Structural Works Construction Duration: A Case Study of Selected Apartment Projects in Addis Ababa
No Thumbnail Available
Date
2020-10
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
There is a recognized need for accurate estimation of construction duration of buildings.
Uncertainties in duration estimation hindered a problem to the construction sector. With
this regard, approximate estimation of the various phases of building construction
indicated to minimize the uncertainty in duration estimation. The structural framework
construction phase covers nearly half of the building project duration. Further, also this
phase almost always present in the critical path of project schedule. With this regard,
accurate and early prediction of structural frameworks duration can help mobilize and
manage resources effectively. Thus, this study provides parametric models that ease this
need.
Case study samples of 41 apartment residential buildings constructed and completed
between a period from 2010 and 2019 were collected using structured questionnaire. 33 of
the sample used to develop duration prediction models using linear regression analysis,
while the remaining 8 samples used to validate developed models.
In order to develop mathematical models first, the interrelationship that exist between
structural works duration influencing factors; project scope factors and quantity of work
items investigated. Project scope factors; total gross floor area, and typical floor area
showed a statistically significant moderate strength positive linear relation. Similar linear
relations were also observed with quantity of work items; quantity of excavation,
formwork, reinforcing bar, and quantity of concrete.
Simple and multiple linear regression analysis carried out resulted in models with low
coefficient of determination. But, best-fit models were developed, by splitting the model
building data set into small-size and large-size projects based on total gross floor area and
removing outliers. More than 85 percent of significant variance in structural frame work
duration by selected project scope and quantity of work item predictor variables was
accounted by best-fit models.
The present study put efforts towards enhancing our understanding of relationships
existing between selected predictor variables and structural works construction duration.
Description
Keywords
structural framework, construction duration, parametric model, quantity of work item, project scope factors