Keywords: Building Information Modeling (BIM), Geometric Algorithms, 3D Modelling
Astract: This work introduces a method for integrating 2d construction documentation-level architectural details into a 3d conceptual model of a building to produce a detailed surface model. The goal is to generate geometry that can be built in the designated material using the appropriate standardized techniques. In the first step, we subject each 2d detail to manual 1d feature extraction to determine those shapes that have an influence on the 3d model. We also extract the sharp features of the 3d model to obtain the building’s skeleton, consisting of edge curves and corners. We perform an alignment of the feature collection obtained from each detail with the 3d skeleton, in accordance with the architectural design. Our goal is to build a 2-manifold with a boundary at each corner of the 3d skeleton. Spanning ruled surfaces between neighbouring corner manifolds completes the final surface model. In this work we focus on the algorithm for constructing the corner manifolds: After the alignment of the feature collections with the 3d skeleton is performed, we calculate a rich descriptor, based on geometric relationship functions, for each feature. In addition, we construct its adjacency graph, containing all other features whose descriptor will change in case this feature is discarded. We then apply simultaneous procedural contraction to all feature collections affecting the same corner of the 3d model. In each step a preservation score is calculated for all features, based on their descriptors. The feature with the lowest score is discarded and the descriptors and adjacency graphs for all others recalculated. This contraction produces ruled surface segments that are eventually stitched together into a 2-manifold with a boundary. We evaluated the algorithm by building a prototype in MatLab and testing it on 170 detail combinations.

Keywords:
Astract: The digital transformation is having a huge impact on many sectors of the economy. Recently, it has gained momentum in the construction industry and in tunnelling in particular. This article explains the challenges associated with the digital transformation of tunnelling and how they are being addressed by a current research project. The project is an inter-university and interdisciplinary project with the aim of advancing digitalisation in tunnelling. The article discusses the topic using various use cases that demonstrate solutions to the current challenges.

Keywords: Building Information Modelling (BIM), Data Drops, digital transformation, Economic and legal issues, Employer's Information Requirement, General
Astract: In the Architecture, Engineering and Construction (AEC) industry, as well as in the tunnelling domain, inter-company processes between partners in different roles in large-scale construction projects still exhibit great potential towards digitalisation. Thereby, information should be seamlessly shared between partners according to the Building Information Modelling (BIM) paradigm. Today, different types of artefacts (e.g., models, plans, documents, etc.) are shared at different points in time, which differ in terms of requirements, information content, as well as data formats. In this article, we extend and prototypically implement the concept of Data Drops to provide those artefacts in a digitalised form via a shared Data Drop management platform. For this purpose, we have developed a formal, well-defined indexed data structure on a metadata level. This not only facilitates traceability, but also enables searching for specific meta-information and provides a common view on Data Drops. In addition, a networked view between different drops can be provided. The approach is being evaluated on the use case of a real tunnel construction project.

Keywords: Construction works, Conventional tunneling, digital transformation, documentation process, General, New Austrian Tunneling Method (NATM), software tool, tunnel process management
Astract: The documentation of the tunneling process is a crucial task of every tunnel construction project. It provides evidence of the work performed and thus, serves as a basis for invoicing and for several further analyses. Therefore, continuous digitalisation of this documentation is essential. For this purpose, we provide a digital Tunneling Information Management System (TIMS), which is a prototypically implemented software tool for replacing the still common paper-based documentation process of tunneling projects using the New Austrian Tunneling Method (NATM). The data model presented here defines the data structures managed by this tool. Based on this, the software architecture and the implementation of TIMS is shown.

Keywords: Augmented Reality, Tunneling
Astract: Tunnel construction is one of the remaining fields that still rely heavily on paper-based processes. Creating paper-based documentation is time-consuming and error-prone. Digitalization can considerably improve these processes. Augmented reality (AR) is one technology that could contribute to this endeavour.AR can deliver information for specific positions in a tunnel through localization automatically. Another benefit of AR is locating virtual information in a real tunnel environment. Due to the large extent of tunnel structures, other technologies for position determination are often inefficient. Despite the enormous benefits of AR, there is little research on this technology in tunnel construction. Therefore, it is unclear whether AR solutions apply to such processes and how to implement them. In this thesis, a focus group interview provided findings on problems in tunnel construction that are improvable with AR. Based on the focus group interview, we selected two problems to improve through AR. We developed two high-fidelity prototypes for the HoloLens 2 to solve these problems: acceptance inspection and tunnel face mapping. Additionally, we developed a solution for localization in the tunnel, which both prototypes utilize. Usability tests give qualitative answers about the usability of the developed prototypes. The tests revealed that usable AR solutions are implementable with current hardware. However, some geometry and user input detection issues by the HoloLens still exist that make it not yet practical enough in real work environments. Furthermore, localization in tunnels with the HoloLens is possible. Regardless, more extensive tests are required to confirm the results for real tunnel construction projects. This thesis serves as a starting point for future research on AR in tunnel construction by providing insights into usability and guidelines for implementing such solutions.