Excavation work takes place almost continually in most cities around the Western hemisphere. Many cities are already full of infrastructures, buried networks, and street furniture, so excavation work is not without any thread to the operator and surrounding environment. Small construction sites, for example, are often constrained by operating infrastructure on surface level and underground. Although different agencies and network owners have information about the location of the objects that put excavation work at risk, this information is not centralized. Different organizations manage location information of buried cables, unexploded ordnance, and pollution, for example. This significantly complicates the early-stage planning and last minute risk assessment processes because professionals need to manually collect, assess, and integrate data about subsurface objects into a comprehensive risk assessment. To smoothen this process, ExcaSafeZone project, therefore, develops a system that collects location data, defines expert-based rules for safety risk assessment, and that synthesizes this into an open source prototype that visualized safety risks on a heat map.@en

This paper presents a process to develop a CityGML-based 3D city model that, together with results from a flood simulation, can be used to investigate direct and indirect effects of floods on a city, its inhabitants and its critical infrastructure, and to quantify such effects by means of a Flood Resilience Score. In addition, the model can be used as a spatial planning support tool for urban planners to prioritise the redevelopment of certain areas and to test new spatial design decisions. First, a semantic 3D city model is prepared and enriched with additional building and infrastructure information. Then a Flood Resilience Score (FReSco) is defined and computed by quantifying the direct and indirect impacts of flooding on buildings, households, and critical infrastructure points using information from both the 3D city model and the flood simulation results. Lastly, a prototype of a spatial planning support tool is proposed to evaluate the flood resilience of a new environmental plan. As a case study, the neighbourhood of “Nieuw Kralingen” in Rotterdam was chosen. Overall, the outcomes of this work are meant to help cities better understand the impacts of flooding and adjust their urban planning activities accordingly. At the same time, the developed methodology also tests the strengths and limits of CityGML-based 3D city models in combination with openly available data and software.@en

A digital twin (DT) can enhance construction management with comprehensive real-time simulations. However, research rarely considers prefabrication factories, whose processes have a significant impact on cost and duration. It remains unclear how construction DTs can achieve their expected benefits without dynamically interacting with the DTs of manufacturing facilities. To address this, a DT integration model is proposed. It builds upon systems theory and describes integration across the three layers objectives, processes, and data & tools. A theoretical example demonstrates potential benefits of integrated DTs. This work can assist researchers and practitioners who are focusing on DTs in the execution phase.@en

The integration of data from a variety of systems is critical for developing smart building applications. Design, construction, maintenance, energy management, and automation data are among few. For this integration, having a comprehensive metadata schema is crucial. Semantic web technologies and domain ontologies have been proposed as a means of modeling and linking domains and their relationships. This study proposes a semiautomatic metadata schema generator that combines an ontology database and a text search engine to generate a metadata schema. The proposed method is tested for a real-world building, and the resulting metadata schema is used to link timeseries data to the sensors and equipment in the building automation system.@en