Generating Sequences of Construction Tasks

Construction processes require preparation phases where among others the sequence of construction tasks has to be developed. This sequence of tasks cannot be transferred automatically from project to project. Specific peculiarities of projects need to be considered so that individual follow up charts need to be set up. In practice, follow up charts are developed that describe the sequence of tasks in different levels of detail. The quality of these follow up charts depends on the experiences of construction managers. Software tools do not support the development process of these charts; they document the result, the follow up charts themselves. Therefore, completeness and logical correctness of these charts can only be checked by inspection. This paper presents a modeling technique where the sequence of construction tasks results from a task-oriented specification. Each construction task is modeled individually by describing its preconditions and its results. The interdependencies between the tasks are calculated from the task-oriented specification based on relational algebra. The task-oriented specification consists of a description of the prerequisites and the results of each task. All interdependencies are calculated based on this specification. A specific topological sort algorithm based on graph theory determines the sequence of tasks. The advantage in using the presented modeling technique is that logical correctness and completeness can be guaranteed. A practical example is