CONSTRUCTION HANDOFF FOR MACHINE CONTROL GRADING. A Case Study of ODOT's I-5: Willamette River Bridge Project Eugene/Springfield, Oregon

Transcription

1 CONSTRUCTION HANDOFF FOR MACHINE CONTROL GRADING A Case Study of ODOT's I-5: Willamette River Bridge Project Eugene/Springfield, Oregon

2 PRESENTATION BY: Tom Metcalf, PE OBEC Consulting Engineers in Lake Oswego, Oregon 14 years of roadway engineering experience Lead Roadway Engineer on the I-5: Willamette River Bridge Project Phone:

3 General Questions of the Audience - Agency staff? - Consultants? - Anyone attend the Aug 2010 Machine Automation Conf in Eugene? - Anyone attend the ODOT Region 1 Brownbag on Machine Control Grading? - Rdwy designers? - Rdwy designers that use InRoads XM? - Anyone ever involved with Machine Control Grading on a project? - Anyone involved in handing over Machine Control Design Data to Construction?

4 Presentation Outline 1. Case Study Background 2. What is Machine Control Grading 3. What is 3D Design 4. How Has Machine Control Grading Changed 3D Design 5. Case Study - Handoff of Machine Control Grading to Construction

5 CASE STUDY BACKGROUND ODOT I-5: Willamette River Bridge Project in Eugene, Or. $150M bridge replacement project Twin foot-long I-5 Bridges 2300 feet of I-5 Roadway and Ramp Reconstruction 2500 feet of I-5 Roadway Work

6 CASE STUDY BACKGROUND How did machine control grading get incorporated into the I-5: Willamette River Bridge project? Project is an alternative delivery project where the prime contractor(hamilton) participates in the design K&E Excavating requested machine control grading to be utilized because of cost savings

7 What is Machine Control Grading? Contractor utilizes 3D design data rather than field staking to construct project elements such as: - Rough grading of earthwork prism - Final grading of earthwork prism - Final grading of aggregate base

8 What is 3D Design? Creates a Model of the Proposed Design Surface using Computer Software - Takes 2D plans and converts it to 3D - Used for establishing a project footprint - Generates earthwork and other quantities - Produces cross sections for construction staking

9 What is 3D Design? ODOT utilizes a 3D design software program called InRoads to model proposed surfaces ODOT now utilizes a newer Past version of InRoads version were not of InRoads as called XM powerful much more powerful and capable of better handling 3D design

10 How Machine Control Grading Changes 3D Design Old industry standard Minimized design effort (save design time and design expenditures) by providing just enough design data for field staff to "fill in the gaps" New industry standard due to machine control grading Increased design effort to eliminate all gaps in 3D design to minimize "field modifications" during construction

11 How Machine Control Grading Changes 3D Design Used to do "close enough" 3D modeling Why? Remember Past industry practice was to minimize design effort (save design time and design $$$) by providing just enough design data for field staff to "fill in the gaps" Examples?

12 How Machine Control Grading Changes 3D Design BEWARE: TECHNICAL CONTENT AHEAD!!!!!!

13 How Machine Control Grading Changes 3D Design Old = Large gaps between template drops New = Smaller gaps

14 How Machine Control Grading Changes REQUIRES CLOSE COLLABORATION 3D Design WITH BRIDGE, WALL AND ROADWAY DESIGNERS Modeling around bridges, abutments and wingwalls

15 How Machine Control Grading Changes 3D Design Guardrail benches, sideslope transitions and structure section transitions

16 How Machine Control Grading Changes 3D Design Some modeling was accidentally overlooked, such as drainage features

17 Effects of Past 3D Design on Construction Projects Need experienced field staff to interpret design for "field fitting" gaps in the design Quantity overages since modeling is not accurately reflecting final field conditions Change orders for "filling in" the gaps in the design REDUCED MORE RISK TO MORE LESS EXPENSIVE = CONTRACTORS PROJECTS FOR ODOT

18 Results of New 3D Modeling Practices on Construction Projects Greatly reduces field interpretation of design More accurate quantities at bidding REDUCED RISK TO CONTRACTORS = LESS EXPENSIVE PROJECTS FOR ODOT This is a proven concept. For a number of years, contractors have been requiring and paying for this level of modeling effort from designers on designbuild projects. Design $$$ < Construction $$$

19 Impacts of New 3D Design on Engineering Efforts Must decide at the beginning of a project to do more detailed modeling Difficult and time-consuming to retrofit a completed project not tailored for machine control grading Introduces need for QA review of modeling Need to account for more design time and design dollars due to added QA effort

20 Construction Handoff of Machine Control Grading Information How does the 3D design get to the construction equipment?

21 Construction Handoff of Machine Control Grading Information Handling/Converting of 3D Design Models Contractors don't use InRoads.they all have different proprietary software Have to convert design models to Proprietary software models for machines to "read" Designer must QC proprietary software models before work begins Increases design time and design expenditures

22 Construction Handoff of Machine Control Grading Information Earthwork Comparison between DTMs and Contractor Files

23 Construction Handoff of Machine Control Grading Information DTM File Naming Convention

24 Construction Handoff of Machine Control Grading Information DTM File Index

25 Construction Handoff of Machine Control Grading Information DTM Index in Plan View

26 Construction Handoff of Machine Control Grading Information Microstation File of All Alignments and Edges of Pavement

27 Construction Handoff of Machine Control Grading Information Annotated Cross Sections on 5 Intervals

28 Construction Handoff of Machine Control Grading Information Annotated Cross Sections for All Non- Roadway Modeling

29 Construction Handoff of Machine Control Grading Information Multiple Design Packages Required Models Broken Up By Design Package

30 Construction Handoff of Machine Control Grading Information Design Changes After Final PS&E Require Remodeling During Construction Can be very time consuming Requires full QC Have to remodel quickly. Contractor could claim delay. Need to account for remodeling effort in Construction Engineering budget

31 Construction Handoff of Machine Control Grading Information Per the Contractor s request, Machine Control Grading was utilized for other design disciplines, such as traffic control plans Converted 2D traffic control plans to 3D staging design Generated models by traffic control stage Generated quantities by traffic control stage Provided x-sections of each traffic control stage

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33 CONCLUSION ODOT's current design software is InRoads XM, and it is more than capable of generating the 3D designs required for machine control grading. This is not a futuristic concept. It has been utilized on a number of past and current projects. Embrace change = Better product = Reduced construction cost to ODOT With Machine Control Grading, Construction handoff is more involved and designer must be engaged throughout construction to remodel as necessary

34 QUESTIONS Tom Metcalf, PE OBEC Consulting Engineers