Information in this article provided by Jaap de Boer, iNFRANEA. For all inquiries or requests to reprint this article, please contact jaap.deboer@iNFRANEA.eu
BIM provides improved constructability for historical landmark in Velsen, Netherlands
Opened in 1957, the Velsertunnel is a railway and motorway tunnel beneath the North Sea Canal in the Netherlands. Rijkswaterstaat, the Dutch government’s Ministry of Infrastructure and the Environment, is in the midst of renovating the automobile section of this aging tunnel. The renovated tunnel will have a higher clearance profile for trucks, new asphalt, and new, modern technical installations, such as CCTV, fire protection equipment, traffic control systems, and ventilation. The escape routes will also be fully updated.
Approx. 65.000 vehicles per day pass through this tunnel and during renovation period it will be closed for 9 months. The renovated tunnel will have a higher clearance profile (>12 cm), renewed asphalt and new state-of-the-art technical installations (e.g. CCTV, fire protection equipment, traffic control systems, ventilation, etc.). The escape routes will also be fully optimized and renewed.
In 2014, Rijkswaterstaat awarded a design/build/maintain contract for the project to Hyacint, a consortium of BESIX, Dura Vermeer, and SPIE, supported by iNFRANEA.
The most unique engineering challenge of this project is to improve a 60-year old highway tunnel, in order to meet modern and unique requirements on specific European tunnel safety rules. The construction itself, including service buildings and ventilations shafts, will not be changed as the typical ventilations shafts are listed in the TOP 100 of Dutch monuments since the rebuilding period 1940 – 1958 and are listed as well as a National Heritage since 2014.
The team scans the historic tunnel for existing conditions. Then takes this scanned data into Civil 3D to create intelligent model. The model-based approach increases efficiency within individual organizations and provided big benefits during coordinated project delivery.
- Compiling input of point clouds, digital elevations and aerial mapping into a single integrated model gave advantages during the preparation stage of the BIM process.
- Model-based design processes are increasing design quality and efficiency, and improving project coordination and communication.
- The integrated model provided more information than drawings. By integrating our BIM processes by means of an intelligent semantic database, we allowed each discipline to connect their particular intelligence to the models. Requirement- and interface management (incl. automated clash-detections), along with document management, all became an integral part of the processes. The semantic database also supports LEAN processes including management of tasks, issues and changes;
- The intelligent semantic database even allowed us to capture the entire project history and to maintain having control of each BIM phase (Configuration Management). We kept track of each revision of each discipline model integrated in the centralized BIM model per LOD;
- The workflow helped us to present any issue to be solved to our client and other stakeholders (e.g. clashes and other conflicts), and became the ultimate communication tool;
- Based on automated tools, we were able to export drawing sheets including relevant data extracted from the sematic database (e.g space parameters, issue reports, quantities) which saved valuable drafting time
Integrated analysis increased the effectiveness of several difficult engineering challenges:
- checking the clearance profile between the tunnel construction, road design and technical installations during all phases in the project;
- increasing the clearance by 12 cm;
- analyzing and optimizing positions of emergency exists;
- checking emergency bypasses in front of tunnel entries.
Communication with models
The typical visualizations, which are part of the BIM processes are mainly used for communication purposes and during design meetings. All specialized engineers have common understanding of any issues and/or decisions important to their internal engineering tasks. It is also the ultimate communication tool to our client The Ministry of Infrastructure and the Environment (Rijkswaterstaat) and other stakeholders involved. Cloud services helped improve collaboration with the entire team working in different locations. The intelligent semantic database combined with BIM was accessible to anyone with the appropriate user rights.
Construction coordination and simulation
The enhanced collaboration among the different disciplines resulted in enhanced visualizations and simulations to check on different requirements. For example checking the emergency bypasses in front of the tunnel entries or the position of Closed Circuit TV (CCTV) cameras. Simulations of the Technical Installations (e.g. CCTV cameras) will become useful to train the Traffic Control Room staff of this tunnel and might also be used to train Emergency staff (e.g. fire brigade, ambulance and police) later.
The 9-month closure of the tunnel will also save valuable time during the construction period. Without this, the project should be carried out in phases which obviously means a longer construction time. Traffic is to be temporarily rerouted to the Wijkertunnel and the Ministry of Infrastructure and the Environment (Rijkswaterstaat) and Environment Department IJmond developed measurements to avoid traffic nuisance by approximately 60 to 70%.
The original construction of this tunnel from 1952 till 1955 is done as cut and cover. The main reason was not to disturb a layer of clay at 16 m minus NAP. Disturbing this layer of clay, would have affected the ecosystem and water resources. Salt water would mix with fresh groundwater. The renovation of the tunnel will also not affect the layer of clay.
The Ministry of Infrastructure and the Environment (Rijkswaterstaat) has an external focus to support the national, regional and local authorities with their activities to reduce CO2 emission, to stimulate renewable energy, to save energy and decrease climate change. They achieve their goals by working together with target groups, making connections by knowledge management and knowledge sharing. Over the last 20 years, the waste and materials department of Rijkswaterstaat has built a solid system for waste management in the Netherlands. Key elements include the national waste management plan and monitoring. In recent years, they have started working more and more towards a circular economy, focusing on material chains and programs about sustainable consumption and production. Rijkswaterstaat is working to improve sustainability performance in infrastructure projects and to use 20 percent less energy.
In this way, Rijkswaterstaat is implementing the government’s policy aimed at green growth. A special developed website (http://www.aanpakduurzaamgww.nl/) helps to find the optimal balance between People, Planet and Profit. Rijkswaterstaat participates in the ‘Green Deal Sustainable Civil Engineering’ initiative closely with clients and contractors to make the entire Civil Engineering sector more sustainable.
Within the Velsertunnel project a very high ambition in the field of Energy & Climate (including use of sustainable and low-CO2 materials) is being pursued. Ambitions include:
- Demolition waste is recycled wherever possible (concrete, fire protection – promat, etc.);
- Local (sustainable) procurement of materials thus also boosting the economy;
- Materials (concrete) savings by using alternative sustainable materials;
- Re-use of existing tunnel systems that are not yet at the end of life;
- Separate disposal of waste;
- There is a ‘sustainability plan’ created as a contractual document;
- Monumental status of the ventilation shafts (maintain look & feel);
- During execution phase as much as possible electrical equipment will be used instead of equipment using fossil fuel.
The entire engineering process in BIM is done before any construction work starts. Any conflicts, which normally would arise during construction, are now solved during engineering as part of the BIM workflow (prior to construction) and will have a positive impact on the construction schedule. We plan to use 4D analysis which will contribute to optimize the project schedule through enabling visual evaluation and comparing different alternative schedules. It will also contribute to optimize site logistics. By automatically generating accurate and consistent 2D drawings, time is significantly reduced and the number of errors associated with generating construction drawings for all design disciplines is reduced.
See the video overview from Hyacint/iNFRANEA
Time and money
The sematic database supports LEAN processes including requirement-, interface- and configuration management and management of tasks, issues and changes. Everybody in the projectteam is using this centralized sematics database and due to the efficiency of all centralized data we were able to reduce project related e-mail by approximately 60%.
By using BIM workflows early in the design stage, enabling us to detect and solve any conflicts before running into them during execution phase, we expect that the overall project cost will be decreased by approximately 5 – 10 %.
Project performance and delivery
The use of BIM and configuration management (based on the intelligent semantic database) resolves problems as transparency, versioning and availability of data. Any problems related to project management and workflow planning, such as undetailed scheduling and difficulties to see the progress of work in individual disciplines, were resolved with the use of collaborative BIM.
The interrelation between the use of BIM as a collaboration platform and the reduction of batch (increment) size in the design process is also particularly of interest, since the collaborative BIM requires more frequent sharing of design data. The more frequent delivery of design data helps collaboration by enabling early cross-checking and analysis of designs.
For the engineering departments BIM provides a basis to develop a better design, consistent construction documentations, and integration and communication among disciplines. Overall Quality Management is improved by design optimization through early discovery of design errors, conflicts and risks.
From the contractor’s (Hyacint) perspective the BIM processes provide better constructability analysis and clash detection. It also helps to improve quantity takeoff and cost estimation, construction planning and controlling, and facilitated handover and commissioning. From the client’s (Rijkswaterstaat) perspective, BIM helps to increase building performance, reduce financial risks, shorten the project schedule, ensure program compliance using the sematic database with regards to requirement- and interface management, and optimize asset management and maintenance. BIM also contributes as a strong communication tool towards stakeholders.