Large Complex Construction Project Schedule Compression Optimization Model With Multiple Sequence Schemes

In recent years,more and more attention has been paid to the great role of infrastructure construction in stimulating economic growth and promoting urbanization in China,which leads to the increasing number of large-scale complex construction projects.The coordinated management of project duration planning and cost control demands higher requirements due to the larger investment,longer construction period and more involved participants.In actual projects,schedule compression is a crucial method to reduce the completion time,which can effectively prevent construction project from delivery delay and eventually earning bonus from early completion.Compressing the duration of large-scale complex construction projects has become more complicated.One key point is that the diversity of construction technology in the large-scale complex construction projects leads to more probability of construction sequences.However,the existing optimization model of schedule compression usually contains only a single construction sequencing scheme and inadequately studies the aforementioned complex temporal and logic relationships,which results in the inability to flexibly represent multiple construction sequencing schemes in one model.In addition,the calculation results possibly miss the most optimal construction sequencing scheme.Therefore,more flexible and adaptable schedule tools should be developed in large-scale complex construction projects with multiple alternatives of construction sequences in order to solve the problems brought by compression optimization of large-scale constructions.This paper focuses on the shortcomings of the traditional schedule tools to deal with schedule the problem of compression optimization.Firstly,in order to enrich the uniform representation scheme of the existing temporal relationships and logical relationships,the “Disjoint” and “IF…THEN” are introduced to represent the separation temporal relationship and dependence logical relationship respectively.Secondly,a set of transformation rules is defined to quickly convert the temporal relationships and logic relationships into the linear constraint inequalities.Furthermore,a schedule compression optimization model based on Mixed Integer Linear Programming is established to calculate the optimal compression scheme.Finally,the model validation for feasibility and usefulness of the proposed theoretical method is conducted by the parameter calculation of a computation example and one case study in the practical engineering.