ZusammenfassungMengen spielen bei der Planung und Ausführung eines Bauprojekts eine zentrale Rolle und müssen effizient, sicher und nachvollziehbar berechnet sowie ausgewertet werden können. Die Mengenermittlungen werden in der Regel in verschiedenen Phasen des Projekts und zu unterschiedlichen Zwecken durchgeführt. Der konventionelle Ansatz zur Durchführung einer Mengenermittlung stellt einen zeitaufwändigen und fehleranfälligen Prozess dar. Relevante Bauwerksinformationen müssen aus Zeichnungen und unstrukturierten Dokumenten extrahiert werden, die möglicherweise veraltet oder inkonsistent sind. Dieses Kapitel beschreibt die Anforderungen zur Unterstützung einer BIM-basierten Mengenermittlung. Die Definition einer klaren Projektstruktur sowie die Etablierung eines transparenten Informationsmanagements ist dabei wesentlich. Zur Organisation der Informationen wird die Anwendung eines projektspezifischen Projektstrukturplans vorgeschlagen. Die Bauwerksmodelle sollten sich strukturell und inhaltlich am Projektstrukturplan ausrichten. Des Weiteren müssen bestimmte geometrische und alphanumerische Informationen enthalten sein. Basierend auf diesen Voraussetzungen wird ein Workflow für eine automatisierte Generierung von Mengen vorgestellt.

ZusammenfassungAnhand der international gültigen Normenreihe DIN EN ISO 19650 sowie der VDI-Richtlinienreihe 2552 werden Konzepte zur Organisation des Informationsmanagements mit BIM im Bauwesen beschrieben. Ein besonderer Fokus wird dabei auf die Auftraggeber-Informationsanforderungen (AIA) sowie den BIM-Abwicklungsplan (BAP) gelegt. Die in den AIA seitens der auftraggebenden Seite beschriebenen Anforderungen werden durch den projektspezifischen BAP, erstellt durch die auftragnehmende Seite, fortlaufend adressiert. Auf Grundlage dieser Dokumente werden die Informationsprozesse in einem BIM-Projekt abgewickelt sowie die modellbasierte Zusammenarbeit organisiert.

Construction Process Simulation in Tunnel Construction – A Prerequisite for Automation Markus Scheffer and Ruben Duhme Pages 1139-1144 (2018 Proceedings of the 35th ISARC, Berlin, Germany, ISBN 978-3-00-060855-1, ISSN 2413-5844) Abstract: Construction process simulation allows producing a virtual copy of an existing or planned construction site. The detailed analysis of construction processes and construction logistics with the support of simulation models creates a better understanding of the performance defining aspects. In many construction sites, the actual performances lag behind the planned levels. This is due to the insufficiency of planning instruments. The authors have performed an in-depth analysis of the internal supply chain of an actual tunnel construction project. While the presented study has focused on the inner outfitting of the existing tunnel, similar work has been done for the excavation processes by the authors. The paper reviews the role, simulation plays for construction planning and investigates the benefits of simulation as a step towards increased automation levels. Keywords: Simulation, Tunneling, Process Modeling, DOI: https://doi.org/10.22260/ISARC2018/0158 Download fulltext Download BibTex Download Endnote (RIS) TeX Import to Mendeley

Buildings become constantly smarter during the last decades. Using sensors, varying information of the building environment, e.g. temperature, energy consumption or building utilization, can be measured and used to improve the user experience. The Internet of Thing (IoT) paradigm increases the number of sources of information from which collect data. However, to store data coming from different sensor systems is still a challenging task. The paper presents an approach for the linkage of sensor data with a Building Information Modeling (BIM)-based building model using the open data format Industry Foundation Classes (IFC). First, based on a research about sensor data and Open Data Models (ODM), the state of the art of possibilities storing sensor data with ODM is described, current advantages and disadvantages are outlined. As an example of the current use of sensor data, the eLUX Lab at the University of Brescia is described. The eLUX lab offers an approach for the connection of sensor data with BIM models. Its usability was proved in case studies and shows, that it is a solid working concept of a static connection. Nevertheless, it can be improved in some aspects. Apart from these optimization opportunities, the concept seems to be well thought out. Thus, it will serve as a basis for the following composed dynamic approach. Especially, the sensor objects of the building information model are well suited for the continued use. With focus on the usage of open data formats, a new dynamic method of linkage using a server platform is developed. Therefore, requirements for the programming of an agent accessing the server and saving the latest sensor data into the IFC file are set. Finally, the general suitability of IFC for the storage and usage of sensor data is described and prospects for the further developments of this approach are given.

Tunnel boring machines require extensive maintenance and inspection effort to provide a high availability. The cutting tools of the cutting wheel must be changed timely upon reaching a critical condition. While one possible maintenance strategy is to change tools only when it is absolutely necessary, tools can also be changed preventively to avoid further damages. Such different maintenance strategies influence the maintenance duration and the overall project performance. However, determine downtime related to a particular maintenance strategy is still a challenging task. This paper shows an analysis of the robustness to achieve the planned project performance of a maintenance strategy considering uncertainties of wear behavior of the cutting tools. A simulation based analysis is presented, implementing an empirical wear prediction model. Different strategies of maintenance planning are compared by performing a parameter variation study including Monte-Carlo simulations. The maintenance costs are calculated and evaluated with respect to their robustness. Finally, an improved and robust maintenance strategy has been determined.

In mechanized tunneling, detailed planning with an accurate performance prediction of the tunnel boring machine (TBM) is needed for a successful tunnel project. Undersized logistical components, disturbances of the supply chain, as well as negligence of maintenance schedules reduce the TBM performance and frequently lead to avoidable times of standstill. This paper presents a performance forecast model for mechanized tunneling projects focusing on wear and maintenance processes of the cutting tools. The developed simulation model has been implemented in the simulation environment AnyLogic using the multi-method approach, including agent-based modeling as well as discrete-event and system dynamic simulation. The model can be used to evaluate different maintenance strategies for a tunneling project. Thus, an improved maintenance strategy for reducing the time of standstill can be found.

Tunnel boring machines require extensive maintenance to provide a high availability. Especially the excavation tools of the cutting wheel have to be replaced timely upon reaching their wear limits. While some jobsite managers choose to only change tools when it is absolutely necessary, others change tools preventively to avoid further damage. Such different maintenance strategies influence the amount of total downtime implicated by tool maintenance. However, it is difficult to determine the downtime related to a particular maintenance strategy analytically. The paper presents a simulation based decision support framework, which determines the amount of downtime that is associated with a certain maintenance strategy. Therefore, a state of the art wear estimation approach for cutting tools in soft ground has been implemented and extended to enable an analysis of the wear behavior under uncertain boundary conditions. This tool can be used to compare different maintenance strategies as well as to improve a given strategy.

INTRODUCTION In recent years, the development of tunnel boring machines has revolutionized the tunneling industry. The general structure of a tunnel boring machine (TBM) can be described as a multi-component system. To achieve high performance rates, machine elements have to perform reliably. Performance losses and interruptions of the construction process should be prevented or at least, reduced to a minimum. In order to achieve high advancing rates, cutting tools must be in good condition at any time. Furthermore, failure of individual tools might result in increased and faster wear of remaining structural components. For this reason, maintaining and replacing cutting tools is crucial to prevent project delays due to insufficient boring performance. Precise prognoses concerning the prevailing geology are infeasible and thus, efficient scheduling of maintenance actions is challenging. The intention of this work is to analyze different approaches of TBM maintenance in soft ground. Different strategies are analyzed by the use of a simulation approach. Cutting tool condition is regarded as performance limiting factor. The maximum operation time of the cutting tools is determined using the “Soil Abrasivity Index”. A case study serves to show the effects of different maintenance strategies on total project duration.

The planning of jobsite layouts and logistics management has a major impact on the performance of tunnel construction projects that use tunnel-boring machines (TBMs). Frequently, projects do not reach the highest possible production performance due to undersized logistics processes or insufficient storage capacities. In this paper, a flexible simulation framework for analyzing interactions between production and logistics processes on tunneling jobsites is presented. A formal ontology for logistic elements on a tunneling jobsite is developed using SysML formalism. Based on this formulation, single systems elements combined in process chains are analyzed and their influence on production processes is evaluated. The formal system description identifies process dependencies and resource constraints of the system elements. These formulations are implemented in configurable simulation components for construction equipment, storage spaces, and production materials. Using these components, a jobsite simulation model can be created. The jobsite layout is represented at a high level of detail, with geometric shapes used for estimating storage capacities and movement durations. This approach uses discrete event and system dynamic simulation and applies probability functions to inputs representing production process times. Dynamic simulation can reveal unknown impacts of logistical processes on the continuous advance processes of the TBM. A simulation model for TBMs is integrated to determine the demand for supply processes. A fast and effective comparison between different jobsite layouts and logistics strategies is possible due to flexible components. By analyzing the workload of construction equipment, robust and efficient setups can be developed. A case study illustrates the usefulness of the simulation framework by comparing the performance of three different jobsite setups for a tunneling project. (C) 2016 American Society of Civil Engineers.

Mechanized tunneling is one of the most common methods used for underground constructions for infrastructure systems. Since a tunnel boring machine (TBM) represents a non-redundant single machine system, the efficiency of maintenance work highly impacts the overall project performance. The wear and tear of cutting tools is a critical, but mostly unknown process. To plan the maintenance work of cutting tools efficiently, it is necessary to know the current tool conditions and adapt the planned maintenance strategies to the actual status accordingly. In this paper, an existing theoretical empiric surrogate model to describe cutting tool conditions will be used and implemented as a software component within a process simulation tool that manages TBM steering parameters. Further, different maintenance setups for TBM cutting tools are presented and evaluated. To prove the capability of the presented approach, a case study will show the effects that improved maintenance work can have on project performance.

Die Produktivität eines maschinellen Tunnelvortriebs ist in starkem Maß von zwei Faktoren abhängig: Der Leistungsfähigkeit der Logistikkette und der Reduzierung der Stillstandzeiten. Insbesondere die Wartung der Abbauwerkzeuge und die dafür erforderlichen Arbeiten in der Abbaukammer sind sehr zeitintensiv und verursachen vielfach ungeplante Stillstände. Aufgrund der Vielzahl an Einflussgrößen und der stark unsicheren Randbedingungen ist eine realistische Prognose der Wartungsprozesse mithilfe der im Baubetrieb üblichen statischen Planungsmethoden nicht oder nur schwer möglich. Hier kann ergänzend Prozesssimulation eingesetzt werden, eine bewährte Methode zur Analyse und Planung von Logistik- und Wartungsvorgängen. Mithilfe eines baubetrieblichen Simulationsmodells können komplexe Interaktionen abgebildet und unsichere Randbedingungen berücksichtigt werden. Es wird gezeigt, wie ein Modell erstellt und zur Bewertung von Wartungsstrategien verwendet werden kann, um die Produktivität eines maschinellen Tunnelvortriebs zu steigern.

Production in mechanized tunneling frequently encounters disruptions due to sensitive process interdependencies. Reasons can be technical failures, insufficient capacity dimensioning, organizational deficiencies, or sensitive supply chains. These unproductive times could be reduced by an adequately designed project setup including logistical aspects. Therefore, possible disturbances must be identified and analyzed in detail. Based on this investigation, the machine and logistics setup can be changed to cope with unforeseen events. We present a modeling and simulation approach to analyze production and logistic processes of mechanized tunneling processes in a transparent and understandable way. The system is formalized in the modeling standard SysML. Thereby, we consider relevant system elements and process interdependencies to assess the effect of disturbances and to identify bottlenecks. We distinguish three kinds of disruptions: i technical failure of main elements related to the production processes, ii issues resulting from an insufficient supply chain, and iii cascading disturbances. The implementation in a simulation environment and the processing of relevant input data are presented hereupon. The presented approach is then illustrated by means of an application example based on a completed metro project. Three extending simulation studies quantify the impact of the identified disturbance categories.

The production cycle in mechanized tunneling with Tunnel Boring Machines depends on numerous processes, ressources and construction materials. Interaction chains of interdepending partial processes make the system sensitive to disturbances or (unplanned) downtime. In order to reduce or avoid standstills, it is essential to analyze the system and its behavior in different tunnel scenarios during the planning phase. Process simulation is an efficient tool to model different parts of a tunneling system, like the TBM, the supply chain as well as different tunneling situations depending on geotechnical conditions. In this publication, the authors present the modelling of a mechanized tunneling project for process simulation, which is capable to consider the effects of different disturbances. Afterwards real data from tunneling projects is analyzed by applying distribution fitting methods. The resulting distribution functions are then used as input data for the simulation model. Based on the input data, selected scenarios are simulated and the results are presented. With these results, productivity and sensitivity can be evaluated regarding the system behavior and strategic solutions for the productivity-oriented dimensioning of the tunnelling system can be developed already in the planning phase.

Many TBM tunneling projects do not reach their planned performance and are struck by severe delays due to deficiencies in their jobsite logistics. The reasons lie within the planning methods which are used throughout the industry. They neither base their estimations on in field measurements nor do they consider the complex interaction of the logistic processes on site. The authors propose a planning approach which is based on a standardized assessment of the logistic equipment and processes and subsequently utilizes process simulation to deliver realistic performance estimates for TBM operations. The approach is demonstrated by analyzing an improvement proposal for a metro construction project with three EPB machines which experiences dramatic logistic problems.

The construction procedure in mechanized tunneling is affected by a complex interaction of logistic processes. Due to restrictive factors (like limited space on construction sites), a just-in-time delivery of material is required for production purposes. Slight differences of the production rate of a Tunnel Boring Machine (TBM) have huge impacts at the logistical chain. Therefore, logistic management is one of the key factors responsible for the success and profitability of tunneling projects. In this paper, a discrete event simulation model is presented that supports tunneling experts in the planning process and can be applied in the construction phase as a tool for decision analysis. Since each TBM is unique, it has a unique demand for logistic solutions. Therefore, the simulation model is implemented in a modular manner such that it can be applied to a vast number of different projects in mechanized tunneling. The properties of the construction site and the TBM are freely configurable. To show the functionality of the model, a fictive demonstration model was conducted. It illustrates the influence of different logistic processes on the production rate of a TBM as well as the complex interactions of single logistic processes in the supply chain of a construction site.

Projects in mechanized tunneling frequently do not reach their targeted production performance. Reasons are often related to an undersized or disturbed supply-chain management of the surface jobsite. Due to the sensitive interaction of production and logistic processes, planning and analyzing the supply-chain is a challenging task. Transparent evaluation of chosen logistic strategies or project setups can be achieved by application of process simulation. This paper presents the continued work of a simulation approach to analyze the complex system of mechanized tunneling. Special focus of this publication lies on the internal logistic as a part of the jobsite supply-chain. The generic implementation allows a flexible configuration of jobsite elements to compare possible setups. A case study demonstrates the approach and highlights the sensitive interaction of production and logistic processes under the influence of disturbances. Additionally, improvements to the original setup of the case study’s construction equipment can be derived.