Optimization of overlapping activities in the design phase of construction projects

Dehghan, Reza; Hazini, Kamran; Ruwanpura, Janaka Y.

doi:10.1016/j.autcon.2015.08.004

Cited by 33 publications

(33 citation statements)

References 29 publications

(89 reference statements)

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“…In other words, unless additional measures (normally involving additional costs) are implemented, theoretically, activities cannot be overlapped to the extent that a successor would start earlier than its predecessor(s), as could potentially occur when a successor's duration exceeds its predecessor's duration. This assumption is in line with previous fasttracking models [20,27,39].…”

Section: 2model Hypotheses and Assumptionssupporting

confidence: 72%

“…In this case, there would be a clear violation (as opposed to a partial override) of the associated precedence relationship. This assumption is also included in most of the recent fast-track models in order to keep the network logic intact [20,26,27,37]. A tighter limit (less overlap) can be introduced, however, if there are other constraints, for example shared resources, space or material handling, between predecessors and their successors [39].…”

Section: 2model Hypotheses and Assumptionsmentioning

confidence: 99%

“…From 2010 to 2015, other group of researchers represented by Dehghan et al [19,20,38] and Dehghan and Ruwanpura [27] In 2016, Gwak et al [39] recently published an "exact" time-cost trade-off computational method to identify the optimum global overlaps between critical activities. It constitutes the latest and most computationally efficient algorithmic implementation of schedule fast-tracking to date.…”

Section: Gwak Et Al (2016) [39]mentioning

confidence: 99%

“…Recently, Dehghan and Ruwnapura [27] and Dehghan et al [20] presented a thorough review of the current and previous fasttracking models for both product development and project design and execution. This review makes no attempt to be as comprehensive, but instead focuses on identifying the most wellknown models and highlighting their major contributions and limitations.…”

Section: 1literature Reviewmentioning

confidence: 99%

“…With regards scheduling algorithms and computational methods, Genetic Algorithms (GA) have been used most frequently in fast-tracking computer applications by researchers as they provide quicker and more accurate solutions in comparison with other non-linear optimisation methods [18][19][20][21]. Mixed Integer Linear and Non-Linear programming models [1], mixed algorithmic approaches (e.g.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Modelling the boundaries of project fast-tracking

Ballesteros‐Pérez

2017

Automation in Construction

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Fast-tracking a project involves carrying out sequential activities in parallel, partially overriding their original order of precedence, to reduce the overall project duration. The current predominant mathematical models of fast-tracking are based on the concepts of activity sensitivity, evolution, dependency and, sometimes, information exchange uncertainty, and aim to determine optimum activity overlaps. However, these models require some subjective inputs from the scheduler and most of them neglect the merge event bias.In this paper, a stochastic model for schedule fast-tracking is proposed. Relevant findings highlight the existence of a pseudo-physical barrier that suggests that the possibility of shortening a schedule by more than a quarter of its original duration is highly unlikely. The explicit non-linear relationship between cost and overlap has also been quantified for the first time. Finally, manual calculations using the new model are compared with results from a Genetic Algorithm through a case study.

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Section: 2model Hypotheses and Assumptionssupporting

confidence: 72%