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1

Digital Design and FabricationOpportunities of improving project design and delivery using Lean and VDC

Samir Emdanat, Director of Virtual Design and ConstructionGHAFARI Associates

Leveraging Virtual Design & Construction for Lean Project DeliveryLean Design Forum ● St. Louis, MO ● June 18, 2009

Elements of Lean

People -> Process -> VDC

In other wordsStep 1: Build a team that believes in Step 2 and Step 3 and a culture of continuous improvement

Step 2: Use Value Stream Mapping to develop a deep and shared understanding of the current processes, (especially the information exchanges between processes) - create a shared vision of target ideal state.

Step 3: Implement process changes and appropriate VDC/automation to eliminate waste in internal processes and at handoffs and keep improving.

Automating an inefficient process accelerates the production of waste.

ALean

System

Peop

le

Technology

Process

2

Lean / VDC for Fast Track ProjectsAccelerated Schedule & 2D Paper Based Approach

Kick-offKick-off

DesignValidationafter Launch

Owner

Contractor

Fabricator

AE

Typical ProcessChangesRe-WorkChanges

Increased Rework

ProductionDelays

Virtual Build

Potential Time Savings

Lean / VDC Approach

Kick-offKick-off Production

Owner

Contractors

Fabricator

AE

Cost of FieldChanges

Design Construction

Design Construction

Manufacturing – 11 completed projects

3

Example: Lean / VDC Process (Steel)

Material Ordered

Material Delivered

CertaintyAbout Design

Certainty about

DetailingDetailing

Fabrication and Pre-

AssemblyJIT

Installation

Ideal State – Lean / Fully Automated Design to Fabrication Process

Steel is one of few building systems where a complete digital workflow from early design to completed fabrication is possible and through available industry standards and technologies.

Yet most projects are delivered using paper drawings.

Example: Lean / VDC Process (Steel)

Manual Material Take offs

Not enough time to

complete design

Detailing done before trade coordination

Late changes

Field changes

Handoff

Paper

Handoff

Paper

Handoff

Paper

Design DetailingShop

Drawing Review

Not enough time for

detailed shop drawing review

Fabrication Installation

4

Example: Lean / VDC Process (Steel)

Why it takes months to prepare and approve shop drawingsFA

BR

ICA

TOR

GC

/CM

ARC

HITEC

T

EN

GIN

EE

R

ARC

HITEC

T

GC

/CM

FAB

RIC

ATO

R

DETAILER

FAB

RIC

ATO

R

DETAILER

~20 days -hand offs

ReviewSubmittal ~15 days -hand offs

Corrections

5

Collision-Free

Target for 80% Clash-FreeProcess Systems Added Steel Detailer’s Model

Certainty: Other Disciplines Design to Fab Workflow

Start 3D Detailing as soon as possible but not before main member design has

completed

Complete all discipline coordination before

steel detailing is completed.

Lean & VDC Results (Manufacturing)

Mill order from 8-14 weeks down to 3 weeks on first project (8 days on later project ~4000 tons).

Shop drawing review time from 10 days to 1 Day (fully in 3D – no paper)

No changes during construction

Early finish (35 Days early) for steel erection

Early finish 27% overall schedule

Steel DetailingBidding – Steel FabricatorDesign/Analysis

A/E Phase

Steel Fabrication, Erection

Shop Drawing Review

Drawings / CDs

Steel Detailing, Fabrication, Erection

Mill Order 8-14 Weeks (Typical)

Steel Mill Order within 3 Weeks (breakthrough using VDC on top of a lean process)

6

Healthcare Integrated Project Delivery

Key project stake holders sign a single contract.

The contract requires:Early commitment to cost and schedule.Shared profit and shared riskUse of leanUse of VDC technologies

The contract does not specify how to get there.

Value Stream Mapping

7

Multi-Discipline Models to Inform Structural Pkg

Real-time Information Access from Multiple Locations

8

Some Early Results 230,000 sqft hospital

Avoided major late changes to early steel/foundation package (e.g. stairs, elevators, corridor widths)

Completed structural design in 8 months

Reduced overall time from start of design to OSHPD approval on first package by 50%

Resolved hundreds of multi-discipline coordination issues early in design.

On track for 3D model based steel shop drawing reviews (no paper).

On track to eliminate MEP submittals.

Made significant progress on model-based estimating

Overall PRE con costs did not increase (tracking less than original baseline).