3D Engineered Models for Construction Part II - Applications

1. 3D Engineered Models for Construction Part II - Applications September 2012

2. Review of Material from Part I • Overview of 3D modeling • 3D plans, electronic data files, digital terrain models • Benefits (to owner-agencies, contractors, and A/E firms) • Use in field applications such as automated machine guidance

3. The Focus of Part II • Successes in implementation of 3D modeling • Specifications (what is used and how) • Project selection guidelines • Information sharing across entities • Common implementation challenges • Limitations to use of 3D modeling (practical examples) • Benefits and future uses (4D and 5D models)

4. History - BIM Applications for Building Construction • Export 3D model to computer numerical control (CNC) machines Photo courtesy of Autodesk

5. History - BIM Applications for Building Construction • Allowed automation of structural shape cuts with a high level of precision • Allowed development of an erection plan and sequencing for implementation Photo courtesy of Autodesk

6. Where Application of 3D Modeling Started • Building Information Modeling • Unusual fabrications • Clashes between items above ceiling tiles (HVAC, piping, etc.) • Vertical construction Photo courtesy of Autodesk

7. BIM Influences on Transportation Applications • Export 3D model to bridge girder fabricators for pre-fabrication • Applies to highways in urban areas where utility networks might have clashes that need to be avoided

8. Further Application of 3D Models to Transportation Projects • Models can support projects in all modes • Example: model transit tunnel system Photo courtesy of Autodesk

9. How 3D Modeling Can Fit Into Agency Programs • 3D modeling can be used by itself or also linked to field applications such as automated machine guidance • Designing in 3D helps practitioners visualize the project and identify potential design issues • The future may see agencies transition to 3D design processes • Accomplishing this transition is the first step (requires software, training, and experience)

10. Use of 3D Modeling with Enhanced Technologies LIDAR – Light Detecting and Ranging (data intensive point clouds for 3D design) Photo courtesy of ILDOT/MO State University

11. Uses of LIDAR for Point Cloud Data for 3D Model • Get clearances for overhead, location of roadside appurtenances, etc. • Nice if dealing with locations with clearance issues, etc. • If need an as-built for a bridge • May be used to evaluate earthwork quantities • Generates robust data for planning design and visualization

12. LIDAR Point Cloud for Overhead Structure Photo courtesy of ILDOT/MO State University

13. LIDAR Point Cloud for Roadway Segment Photo courtesy of ILDOT/MO State University

14. LIDAR and 3D Modeling CAD/Design Data LIDAR Point Cloud Photos courtesy of Autodesk

15. Bridge LIDAR Video Example • LIDAR point cloud 3D video visualization fly-by Photo courtesy of Autodesk

16. Wisconsin DOT – US Hwy 10 Expansion • Model based design allowed for faster, cheaper plan set development compared with traditional CAD design Photo courtesy of Wisconsin DOT

17. Project Selection Guidelines • Eventually all projects may be in 3D • Advantages – where a lot of stakeholder input is expected • Projects with high probability of clashes • Where a considerable amount of earth moving may be required (use of AMG)

18. Project Selection Guidelines (cont.) • Where string lines are going to be problematic • Pavement projects where surface problem corrections (severe undulation) require variable milling to improve the ride • What other project selection criteria have you used?

19. AMG Specifications • Agencies may wish to avoid requiring the use of AMG, unless it is absolutely necessary for the success of the project (e.g. single lane white topping and pilot implementation projects). • Do not want to limit potential bidders by specifying a method that only a few can use.

20. How Agencies Handle Specification Needs • Often will not spec 3D modeling but allow contractors to use this innovative technique for greater efficiency and lower cost • Some have a spec in case the contractor decides to use AMG • The spec is only used if the contractor chooses to use AMG as part of the bid • Encourages contractor to use AMG which would require a specification (QA requirements, how they will get the model, what they will do with it, waivers needed to get the model, etc.)

21. Communicating Information and Data • 3D model is provided by agency • Contractor hires a company to process data into machine file for use in the field • The contractor may handle 3D modeling using their own personnel

22. Limitations to Use • Model is a representation • Data intensive • Time limitation • Governmental agencies may be inundated with requests for information in order to complete data prep on time

23. Changes in Surveying • Augments an original survey that is performed • Grid survey as opposed to centerline survey

24. Transfer of Model from Designer to Constructor • Contractors prefer • As detailed as possible • Before bidding • Modifications will have to be made • Can a modified model be treated like a shop drawing? • What constitutes a design modification and therefore requires a licensed professional and coordination with the original designer? • What modifications merely add detail that carries out the original design intent?

25. AASHTO Resource for Application (TIG) • Integration of 3D Modeling, GPS, and computer operated construction equipment

26. Opportunities and Challenges Photo courtesy of Autodesk

27. Common Challenge • Deciding how much detail to provide Image courtesy of FHWA

28. Data • Improve data management and exchange • XML and TransXML need to be more robust for wide adoption • Standard procedures needed to pass files between designer and constructor

29. Training • Training and education needed for all • Stakeholders (owner, designer, constructor) • All levels • Designers and design technicians • Engineers and managers • Executives

30. Standardization • Standardize practices and processes agencies use during modernization process. • Delivery of model to constructor • Project survey control • Techniques to survey for partial payment of quantities • Requirements for the 3D model – CADD standards, design manuals, etc.

31. Benchmark Case Studies • Case studies demonstrate • Feasibility • Best practices • Contracting authorities wish to see success in a context that is similar to their own • May encourage adoption

32. Subgrades/Paving/Overlays • Unique challenges that are different from earthwork applications • Greater accuracy required • Higher value materials • Perishable materials • Thickness and ride are more important than elevation sometimes

33. The Future of 3D Modeling • 4D models add schedule components

34. 5D Model (Cash Flow) Photo courtesy of Autodesk

35. Summary • Application of 3D modeling for transportation can follow BIM applications used for buildings • Models can provide cost savings, time savings, and clash detection for items such as utilities • Technology applications such as LIDAR can provide robust data to supplement the 3D model

36. Questions? Douglas Townes, FHWA-RC 404.562.3914Douglas.Townes@dot.gov Richard McDaniel, FHWA-EFL571.434.1580Richard.Mcdaniel@dot.gov Chris Schneider, FHWA-HQ202.493.0551 Christopher.Schneider@dot.govBryan Cawley, FHWA-HQ202.366.1333 Bryan.Cawley@dot.gov