الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
Building Information Modeling (BIM) is defined as the process of design,
construction and use of the building or facility infrastructure using
information about virtual objects.
Previous studies concluded that BIM implementation resulted in increasing
the design cost by 6.5%,11% and 17% for Schematic Design phase, Design
Development phase, and Construction Documentation phase, respectively.
However, there is still a need to compare between BIM and CAD
technologies relative to budgeted and actual man-hours.
On the other hand, Lean construction refers to the application of lean
thinking or lean principles on projects in the construction industry. The
Construction industry is different in many ways from the Manufacturing
industry. The unique and complex nature of the construction industry
presents an immense challenge for the application of production
management, as it would not be easy to simply transfer management
practices from production to construction unless modifying construction
management methods and culture.
BIM and Lean are quite in concept. However, it has been established that
a synergy exists. The objective of this study is to compare between BIM
and CAD technologies in different kinds of projects, relative to budgeted
and actual man-hours, to develop a Design Estimate that could predict the
estimated man-hours for BIM based projects. The significance of this study
is the value of the comparison and its reflection in estimating man-hours
with an acceptable accuracy based on data collected from BIM projects,
which could affect the bidding process. Another objective of this study is
vi
to attempt to apply Lean Approach to the design phase of the construction
projects to enhance its performance.
Data of 40 projects designed in the last 10 years were analyzed in order to
develop the Design Estimate. The results showed that there was a 4.6% and
+7.0% difference between the estimated and the actual man-hours for
Residential buildings type, and a +7.6% and -5.0% difference between the
estimated and the actual man-hours for commercial buildings type, with a
reasonable error rate considering the limited number of collected BIM
projects.
Meanwhile, Delays have become a universal phenomenon, resulting in
time and cost overruns in most cases, although schedule delays seem to be
embedded in all projects, identifying the main causes and preventing these
problems from occurring are better than resolving subsequent delay-related
disputes. Lean approach provides an informative guidelines to waste
reduction or even elimination if properly adopted. In this study, the Pareto
chart was used in order to highlight the main causes of delay in the design
process, and the results of the Lean Approach implementation indicated
that about 28% of the total number of delay causes resulted in about 73%
of the causes of delay of the projects when using the frequency of
occurrence as the Defects, also, about 23% of the total number of delay
causes resulted in about 77% of the causes of delay of the projects when
using the delay duration as the Defects. Finally, the overall performance
improvement ranges between 3% and 34% by solving about 23% of the
total number of delays.