A FRAMEWORK FOR THE REPRESENTATION OF TWO VERSIONS OF A 3D CITY MODEL IN 4D SPACE

3D city models are being increasingly adopted by organisations in order to serve application needs related to urban areas. In order to fulfil the different requirements of various applications, the concept of Level of Detail (LoD) has been incorporated in 3D city models specifications, such as CityGML. Therefore, datasets of different LoDs are being created for the same areas by several organisations for their own use cases. Meanwhile, as time progresses newer versions of existing 3D city models are being created by vendors. Nevertheless, the existing mechanisms for representating multi-LoD data has not been adopted by the users and there has been little effort on the implementation of a mechanism to store multiple revisions of a city model. This results in redundancy of information and the existence of multiple datasets inconsistent with each other. Alternatively, a representation of time or scale as additional dimensions to the three spatial ones has been proposed as a better way to store multiple versions of datasets while retaining information related to the corresponding features between datasets. In this paper, we propose a conceptual framework with initial considerations for the implementation of a 4D representation of two states of a 3D city model. This framework defines both the data structure of such an approach, as well as the methodology according to which two existing 3D city models can be compared, associated and stored with their correspondences in 4D. The methodology is defined as six individual steps that have to be undertaken, each with its own individual requirements and goals that have to be challenged. We, also, provide some examples and considerations for the way those steps can be implemented

Geobim for digital building permit process: Learning from a case study in Rotterdam

Among the digitalization processes which are being raised in Europe and in the world, the building permit process is seen as one of the priorities by municipalities, governmental institutions and standardization organizations. However, in current practice, the building permit issuing as well as the integration of geoinformation with BIM (GeoBIM) suffers from a number of complex sub-issues. These issues still remain and prevent the development of successful methodologies. In this paper, the building permit use case is explored within a project in close collaboration with the municipality of Rotterdam. A very specific case study in Rotterdam was selected as a starting point, which allowed us to develop the needed methodology for the implementation of an effective tool. In this paper we highlight the interpretation and formalization of regulation for building height, overhang and tower ratio. While these rules are specific to a zoning plan in Rotterdam, we believe that the methodology and encountered issues in formalizing the rules, applying the rules on delivered models and integrating various data sources (BIM and GIS specifically) are general to most building codes

EuroSDR GeoBIM project a study in Europe on how to use the potentials of BIM and GEO data in practice

In both the Geo and BIM domains, it is widely acknowledged that the integration of geo-data and BIM-data is beneficial and a crucial step in facing the multi-disciplinary challenges of our built environment. The result of this integration - broadly termed as GeoBIM - has a range of potential uses from district study to road safety. However, from the data perspective, this integration raises the question of how to integrate very detailed design and construction data from the BIM domain with contextual geospatial data (both 2D and 3D) that model a very diverse range of aspects of the wider built and natural environment. This paper reports work carried out during the second phase of the EuroSDR GeoBIM project, which sets out to understand the general status of GeoBIM across Europe with particular focus from a National Mapping and Cadastral Agency perspective. The first phase of the project reviewed the current status of GeoBIM in participating countries and identified the need for specific detailed use cases to overcome both the lack of awareness and the lack of understanding of the potential of GeoBIM. We present both an update on the current status of GeoBIM, and additional details of one of the selected use cases relating to planning/development permits. For the latter, we have been able to develop a detailed workflow highlighting specific data exchange points within the process to issue a development permit, allowing a more in-depth identification of both the roles and data needs at each stage

GeoBIM Benchmark 2019: Intermediate results

An investigation into the implementation state of open standards in software is currently ongoing through the ISPRS/EuroSDR 'GeoBIM benchmark 2019' initiative, which kicked off earlier this year. The benchmark activity provides a way of assessing and comparing the functionality of different software packages in GIS and BIM in terms of their ability to handle standardised data (IFC and CityGML) and undertake various tasks using this data. Approximately 65 people have registered to participate so far, with participants from a wide range of backgrounds and proposing to test a variety of software packages. This confirms that the issues under investigation are of interest, and also meets the wider benchmark aim of having a variety of participants, since the project is conceived as using a bottom-up approach with cross-disciplinary and cross-expertise participation. While full benchmark results are not due to be submitted until later this year, interim results have highlighted a number of common issues across multiple software packages, and a web meeting for participants held in July 2019 also led to some improvements in how the benchmark results are being captured

Geobim benchmark 2019: Design and initial results

GeoBIM, the integration of 3D geoinformation (Geo) with building information models (BIM), is a subject of increasing attention in both domains. A well-known practical challenge for this integration is the mixed state of software support for open standards in each domain that would ease the integration. This is often known by practitioners but poorly documented. In order to solve this problem, we devised the GeoBIM benchmark, in which we compile the experiences of volunteering participants, who perform a guided study to test the software they are most familiar with against a few provided datasets structured in open standards. The aim of the tests is to improve the knowledge of the state of the art in the software support for GeoBIM open standards and to identify points for improvement. In this paper, we present the design of the benchmark, especially explaining and discussing the chosen data to be used with their connected issues to be tested, and some initial results

Opportunities and challenges for GeoBIM in Europe: developing a building permits use-case to raise awareness and examine technical interoperability challenges

The integration of geoinformation with BIM (GeoBIM) is critical to underpin solutions to many city-related challenges. However, to achieve an effective integration it is necessary to consider not only data and technical options but also current practice and users’ needs. This paper describes work carried out within the EuroSDR-GeoBIM project to address this challenge. After investigating potential uses for GeoBIM and existing challenges, we address a planning permits for buildings use case, to help bridging the gap between theory and practice. The resultshighlights a high-level harmonised workflow envisaging the use of GeoBIM information for automating the planning permits process

THE ISPRS-EUROSDR GEOBIM BENCHMARK 2019

Standardised data formats and data models are essential for data integration and interoperability, which in turn adds value to data by allowing its reuse in multiple contexts. For this reason, in recent years extensive efforts have been focused on standards development. When representing the built environment, 3D city models and Building Information Models are particularly relevant, and their integration is now required to underpin use cases that cover the full life-cycle of a built asset, including design and planning as well as operations and management, and to support legal applications such as cadastral systems. For those kinds of data, CityGML by the Open Geospatial Consortium and Industry Foundation Classes by buildingSMART are the most popular reference standards. However, many users report, often through informal channels, the difficulties of working with these formats. This paper summarizes the outcomes of the GeoBIM Benchmark 2019, a scientific initiative funded by ISPRS and EuroSDR to collect insights into the most relevant issues encountered in the management of CityGML and IFC within existing software. Alongside data management (import, visualisation, analysis, export) problems, issues of particular consequence in terms of integration relate to georeferencing IFC files and the conversions among the two kinds of formats and models. Thus, the benchmark was designed to explore these tasks in available software. Following analysis of the benchmark results, a key outcome is the impossibility to find clear patterns in the behaviour of tools, which consequently means there is no consistency in the implementation of standards. Although the results could seem disappointing, the criticality in managing these standards as they are was described and this awareness can be the starting point for further research or further standards development. Finally, this project was useful to gather a wide community around this topic, and the discussion about the GeoBIM-related issues was definitely pushed

PREFACE

The annual 3D GeoInfo Conference aims at bringing together international state-of-the-art research and facilitating dialogue on emerging topics in the field of 3D geoinformation. On the 1st and 2nd of October 2018, the 13th 3D GeoInfo conference was organised at the Delft University of Technology. On this occasion, the topics included 3D data collection and modelling, reconstruction methods for 3D representation, data management for maintenance of 3D geoinformation or 3D data, applications of 3D geoinformation, and visualisation.This volume of the ISPRS Archives is composed of 9 full papers that received positive double-blind peer reviews, as well as the 24 papers that received positive double-blind reviews as abstracts and were then extended into papers. The 12 full papers with the most positive reviews were instead published in the ISPRS Annals. We hope that the papers in this special issue will inspire decision-makers, academics, engineers, computer scientists, land surveyors, urban planners, and students interested in the 3D geoinformation domain. We would like to thank all the authors, the reviewers, and the organising committee for their valuable contribution towards this publication. We would like to acknowledge that we have received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 677312 UMnD: Urban modelling in higher dimensions).</p

PREFACE

The annual 3D GeoInfo Conference aims at bringing together international state-of-the-art research and facilitating dialogue on emerging topics in the field of 3D geoinformation. On the 1st and 2nd of October 2018, the 13th 3D GeoInfo conference was organised at the Delft University of Technology. On this occasion, the topics included 3D data collection and modelling, reconstruction methods for 3D representation, data management for maintenance of 3D geoinformation or 3D data, applications of 3D geoinformation, and visualisation.This volume of the ISPRS Annals contains the 12 full papers that received the most positive double-blind peer reviews from the Scientific Committee of the 3D GeoInfo Conference. The other 33 presented papers are published in the ISPRS Archives.We hope that the papers in this special issue will inspire decision-makers, academics, engineers, computer scientists, land surveyors, urban planners, and students interested in the 3D geoinformation domain. We would like to thank all the authors, the reviewers, and the organising committee for their valuable contribution towards this publication.We would like to acknowledge that we have received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 677312 UMnD: Urban modelling in higher dimensions).</p

Opportunities and challenges for GeoBIM in Europe: developing a building permits use-case to raise awareness and examine technical interoperability challenges

The integration of geoinformation with BIM (GeoBIM) is critical to underpin solutions to many city-related challenges. However, to achieve an effective integration it is necessary to consider not only data and technical options but also current practice and users’ needs. This paper describes work carried out within the EuroSDR-GeoBIM project to address this challenge. After investigating potential uses for GeoBIM and existing challenges, we address a planning permits for buildings use case, to help bridging the gap between theory and practice. The resultshighlights a high-level harmonised workflow envisaging the use of GeoBIM information for automating the planning permits process