Emergent models in integration Nature as model: Declaration of interdependence Lean thinking Building information modeling Lean thinking

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1 Emergent models in integration Emergent models in integration Nature as model: Declaration of interdependence Lean thinking Building information modeling Lean thinking A substantially Building information new manner of modeling thinking is required if mankind is to survive. -Albert Einstein From Laura Lesniewski, BNIM Architects

2 Contribution of buildings in the U.S. 65.2% of total U.S. electricity consumption >36% of total U.S. primary energy use 30% of total U.S. greenhouse gas emissions 136 million tons of construction and demolition waste in the U.S. (approx. 2.8 lbs/person/day) 12% of potable water in the U.S. 40% (3 billion tons annually) of raw materials use globally - U.S. Green Building Council

3 Topics Detailing in the model on the Terminal 5 project Model-based design of construction operations on the Channel Tunnel Rail Link project Impact on construction performance of computer modeling and lean project delivery on the Camino Medical Center project Computer modeling at Burt Hill Architects and Engineering Virtual Design and Construction Task Force recommendations

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5 Notes on Original Process Six weeks lead time for detailed design drawings Only product design criteria applied in the design step Sequential processing: builder reviews found problems which led to rework which extended the lead time which increased the problems.

6 Rebar Production Process & CONWIP Control Pull Engineering Fabrication & Assembly Installation 3 Days 2 Days 2 Days ProjectFlow

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10 Notes on Current Process Structural engineer produces General Arrangement drawings using AutoCad, with some preagreement on principles of buildability Detail design is also 2D from AutoCad, but with some builder input Digital prototype is produced collaboratively by engineer, detailer, modeler and builder using CAD/CAM software Clash and integrity check: If can t build it in the model, then can t build it on site Rapid response to changes Can pull detailing to installation Can pull fabricated components and subassemblies

11 Notes on Future Process Collaborative design and DfX Further developed and completely shared design criteria: buildability, sustainability, durability, etc. Engineer consults with builder before designing Better tools; e.g., parameterized designs and immersive visualization

12 Case Study Fleet Sewer Possession Scope: Remove crash deck Install temporary steel supports Install 7 sections of Orthotropic deck Earth and Bond Orthotropic Deck Install 2 Plate Girders (65 & 105 Ton) Install 5 ea 30 Tonne M-Beams Schedule: 51 Hours to Execute Work $350K Per Hour Liquidated Damages Many (project team members) believed that this process and volume of work in the time available to be impossible $1.7 million per Day Liquidated Damages Approach: SPS Production Manager to plan and control production Create 3D model and link to SPS Production Manager to support computer based process engineering

13 Create Master Schedule for Works Rail Possession completion milestone date used and schedule was produced working back SPS Production Manager used to ensure everything needed for possession was in place by the time of the possession start SPS Production Manager also used to ensure proper execution during possession period

14 Integrate Design Using 3D Digital Build

15 Validate Design Cross Section from 2D Design Drawings Fabrication: $250,000 Transportation: $6,500 Equipment: $115,000 Cross Section from I-DEAS 3D Model Labor: $18,500 And it doesn t TOTAL: $390,000 fit!

16 Validate Proposed Sequence (4D Simulation)

17 Camino Medical Center

18 Camino Medical Center Impact of VDC on the Project Benefits: HVAC HVAC sub developed more confidence that what they were pre-fabricating would fit in the field as the coordination proceeded and they did not see any issues on the first few quadrants. This led to improved prep for shop fab for building and assembling duct fittings HVAC duct is coming out in larger sections, requiring less assembly on site and more offisite Speed of field installation for HVAC due to accuracy of 3D coordination HVAC has seen close to % of schedule improvement using less crews than originally planned

19 Camino Medical Center Impact of VDC on the Project Benefits: Electrical Subcontractor able to do more prefab work earlier, at lower labor rate Spent less hours on the job and more offsite using less expensive labor workforce in a more controlled environment 8000 manhours in offsite fabrication versus hours of onsite work 40,000 onsite manhours would have been required on this job Less waste in materials. Would normally not cut exact lengths of MC cable on a project like this but they are doing that on Camino

20 Camino Medical Center Impact of VDC on the Project Benefits: Plumbing Subcontractor on a normal project would only prefab 50% of pipe on the project, with 3D coordination they are pre-fabricating everything possible Plumbing was able to account for the lower labor quality with a very accurate prefab and more of a bolt in place system that could be done by lower quality workforce For plumbing the quality of workforce has become an issue in the San Francisco Bay Area

21 Using the BIM Model for Many Purposes Rapid design exploration Design communication and visualization Integrated 2d documentation/schedules Specs generated from model Integrated program areas (scope control) Analysis and simulation Rapid prototyping Quantifications/cost estimating Logistical planning and schedule integration From Burt Hill Architects & Engineers

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25 VDC Recommendations-Role of VDC in Lean Project Delivery 1. A Problem of Workflow The problems we face are a matter of work flow and cannot be solved by layering on VDC as a technology on top of current project delivery. Otherwise, we will automate waste. 2. Reciprocal Dependencies VDC models require and pull design information that exposes reciprocal dependencies that are not typically identified in current design planning. 3. Pre-fabrication Program Do not waste this opportunity!

26 VDC Recommendations-Forming & Working in the Team 1. Work in Cross-Functional Teams 2. The Big Room 3. Team Make-up 4. Leveraging Experience 5. Multiple Models 6. Plan & Manage with the Last Planner System