title: Understanding complexity at pre-construction stage of project planning for construction projects
Creators: name: Barani Shikhrobat, Mehran
Publisher: name: University of Reading
Year: 2023

description: The research focus is on understanding the impact of complexity on the planning of 
construction projects at the post-contract award stage prior to work commencing on site. 
Complexity is the state of something having many parts that makes it difficult to understand 
the interactions and impact when devising a plan. Understanding the complexity of a 
construction project, especially at the pre-production stage of the project management life 
cycle is challenging because of uncertainty and risk. Several small and large projects are 
failed because of a lack of data, information, and knowledge of project complexity. Current 
planning tools and techniques are deterministic in nature (Gantt chart, CPM, PERT) 
assumptions and estimates are made, whilst applying little probability of completion for each 
task. Every project embodies assumptions and influences and should start with a complete set 
of clearly defined goals and constraints that remain constant throughout the duration of the 
project. Projects are not fully designed at the outset because of the nature of the construction 
process with many uncontrollable issues. Construction planners continue to apply the 
traditional methods and tools of “hard” project management that were developed for “ideal 
projects”, neglecting the potential influence of complexity on the design and construction 
process. 
Understanding the concept of project complexity is not new, but it has increased in 
importance. There is not a unique definition for the term of project complexity, consequently 
this makes quantification and measurement more difficult. 
Project complexity originates from different sources of environment, technical, and workflow 
interactions. They can be divided into two categories of complexity factors, firstly, project 
tasks, and secondly, project organisation and management. Project tasks may originate from 
performance, lack of resources or environment changes for a specific task. Complexity 
factors that relate to organisation and management refers to workflow and interdependence of 
different parts. Complexity is found as the basis of shortcoming that traditional tools and 
techniques were not being able reflect it in the calculations for expectations. However, the 
impact of the complexity on expectations for the total project duration at the pre-plan stage is 
not known which is remarked in this research. 
This research investigated the emergence and growth of complexity on project scheduling
and provides a model to consider the influence of complexity on the total project duration at 
the post contract award pre-construction stage of the project. 
Therefore, this research focus in on understanding the fundamental causes of 
complexity on construction projects and understand how it might be possible to consider 
complexity in expectation. The investigation is supported by using different technique to 
gather the view of experts and measure the weight of each defined factor in the proposed 
model. 
The results were used to develop a model that considers the core complexity factors 
and their interactions. A linear regression analysis used to define the direction of those 
interrelated factors. System dynamics used to model and consider the influence of complexity 
on the expectations for project scheduling at pre-plan stage. Feedback from experts revealed 
20 major complexity factors that impact project planning. 
The factors are divided into 5 categories known as core complexity factors. To 
understand the weight of each factor in comparison, AHP analysis method is used. The 
comparison shows that externalities is ranked as the highest influence across the complexity 
factors. The research underlines that there are many internal and external factors that impact 
project activities and the project overall. Despite the focus of previous research on 
considering complexity and optimisation for each individual task, this research shows the 
importance of considering the influence of complexity on the project master plan undertaken 
at the post contract award pre-construction phase of a project.