ABSTRACT
Visual 4D modeling and planning technologies have recently begun to play a crucial role in the realization of complex construction projects and programs. They enable to improve communication and coordination among stakeholders and, thereby, to reduce risks and waste during the project implementation by means of simulation and visualization of project activities in space dimensions and across time. Modern project modeling systems possess some underlying functions for such purposes, but are still limited in reasoning capabilities necessary for automated validation of the project schedules in terms of their feasibility and absence of spatial-temporal conflicts. Basically, these are collisions and interferences of construction objects, missing collision-free paths to deliver the objects to destination positions in planned time, and invalid schedules leading to the objects hanging without any reliance. A software library providing advanced capabilities for spatial-temporal modeling and reasoning is presented in the paper. The library called Constructivity4D supports a representation of all of the core concepts in the scene modeling and possesses a wide range of operators and validation functions. The modeled dynamic scenes are suggested to be hierarchically organized with the objects obeying particular behavioral patterns. Being compliant with popular qualitative reasoning formalisms and relation algebras, the supported operators and functions can be combined to identify non-trivial spatial-temporal conflicts originated from the construction project validation problems. The paper discusses the design considerations of the library, its functionality, interfaces. Particular attention is also paid to applied computational methods and implementation details.
