DEVELOPMENT OF A SOFTWARE APPROACH TO IDENTIFYING TIME-SPACE CONFLICTS AND ASSESSING THEIR IMPACT ON LABOR PRODUCTIVITY IN BUILDING CONSTRUCTION

Space is considered a signicant and eective resource and constraint in building construction projects. In order to execute project activities, other resources, such as labor, machinery, equipment, and material, require space. In other words, each activity needs dierent types of space. In case the space constraint is neglected, resources allocated to two or more activities, will be obliged to work in a common area during at least a portion of activities duration. Con ict among spatial requirement of activities, can cause serious problems in their execution. Nowadays with the considerable increase in demand for early completion of projects, in many cases the project schedule is compressed. Schedule compression is also used for the purpose of delay compensation. "Fast tracking" or the parallel execution of previously sequential activities, is among the common methods to shorten the project schedule. In case of fast tracking, more activities will be executed concurrently. Therefore, con ict among their spatial requirements will be more likely. Physical con icts among concurrently executed activities are referred to as \time-space con icts", and these con icts are among the most eective factors in labor productivity decrease in building construction projects. They can also seriously impact other performance indexes such as time, cost, quality, and safety. Thus, development of ecient methods and tools for workspace planning can have a signicant eect on project performance. In the present research, considering the mentioned necessity, the signicance of space as a resource and constraint in building construction projects is studied, and various types of space and space requirements in building construction projects are identied. Furthermore, a 4Dbased software approach is developed to identify potential time-space con icts in the schedule and assess their impact on labor productivity. This approach makes con- ict identication and assessment of its eects possible. Through this approach, with the use of proper solutions, the number of potential con icts will be reduced before the start of the construction phase; therefore, an optimized schedule is resulted.