Knowledge-based Engineering for Infrastructure Facilities: Assisted Design of Railway Tunnels Based on Logic Models and Advanced Procedural Geometry Dependencies

The current design of infrastructure facilities is mainly driven by the application of guidelines, codes and international standards. The complex interpretation and geometric representation of those rules impedes the dynamic search for alternative solutions. Parallel to this, in recent years there has been an increasing tendency toward the adoption of 3D modeling solutions. Of particular benefit in the design of infrastructure facilities is the use of parametric modeling systems since they allow the definition of flexible models that can easily be adapted to satisfy changes in the boundary conditions. By defining dependencies and constraints, engineers are able to capture the underlying engineering knowledge in the parametric model. However, the design knowledge that can be defined by those instruments is limited to a reduced number of constraints and simple algebraic relations among parameters that are clearly insufficient to describe the complexity of engineering rules. To close this technological gap, this paper presents a novel knowledge-based engineering (KBE) approach that captures the design knowledge engineers apply in the interpretation and generation of infrastructure models based on rules specific for infrastructure facilities. To achieve this, distinct knowledge units named logic models capture the generation knowledge needed to convert the abstract information engineers must deal with into a corresponding parametric geometry model. In addition, this paper presents a methodology to integrate logic models with parametric design systems. To this end, logic models are introduced as a new set of domain-specific features responsible for the generation and management of the geometry, connecting the results with other part of the model by advanced procedural geometry dependencies. Finally, the proposed methodology is verified in a real case study for a suburban railway tunnel that is in the planning stage in the city of Munich, Germany. The paper concludes with a detailed discussion of the proposed approach and an outlook on future developments.