Fredric L. Plotnick, Ph.D., Esq., P.E. Engineering & Property Management Consultants, Inc.

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1 Introduction of Relationship Diagramming Method (RDM) Variant of the Critical Path Method of Planning & Scheduling Analysis to Primavera Pertmaster Fredric L. Plotnick, Ph.D., Esq., P.E. Engineering & Property Management Consultants, Inc

2 Origin of the Problem

3 Evolution of CPM

4 Evolution of CPM 950 s 90 s 970 s 980 s 990 s 000 s

In practice, this meant deliberately limiting the use of the "flexibility" features.

5 In the early days of CPM, computing capability was at a premium. Rooting out inconsistencies in scheduling data had to be left completely to the planner. In practice, this meant deliberately limiting the use of the "flexibility" features. Today, the desktop computer I'm using to compose this letter has far more capability than the UNIVAC we used for our first CPM calculations. Thus, there is no reason why the computer cannot be programmed to tell me that my scheduling input is inconsistent and why.

6 Scheduling Resources is Not CPM Notice to Proceed 0 Foundation Excavation 5 Resources FS FS FS FS Foundation Backfill

7 Plan then Schedule Notice to Proceed Foundation Excavation Cure 0 5 Cure Cure Cure Foundation Backfill Notice to Proceed 0 Foundation Excavation 5 FS FS FS FS Foundation Backfill

8 Plan then Schedule Notice to Proceed Foundation Excavation Cure 0 5 Cure Cure Cure Foundation Backfill Notice to Proceed 0 Foundation Excavation 5 FS FS FS FS Foundation Backfill

9 What can we do? Maths of 50s watered down to 50s computers PCs provide tools (but not skills) to the masses More powerful PCs benefit glitz not maths GUI and WYSIWYG i/o favors bar charting Wizards further reduce need for skills Where is the logic?

10 Proposed Solution RDM Relationship Diagramming Method

11 Introduction by James J. O Brien Improving CPM Restoring the Original Promise Video on next slide Kelley expected more from CPM but was limited by early computers free and independent float RDM created ~ 003 to 005 amazing grasp of the obvious what Kelley was looking for

12 Relationship Diagramming Method more about RDM requires you to record the relationships between activities and allows the computer to recalculate the impact of changes made reducing the 40%+ rework effort to that of a keystroke

13 Relationship Diagramming Method Five classes of new coding: The Event Code The Duration Code The Reason Why Code The Expanded Lead Lag Code The Relationship Code

14 Reason/Why Codes Record the reason why the restraint exists physical how important description resource crew/craft/equipment/forms/materials/etc. Excav 000 feet - 0 days P st / last 50 feet Stone 000 P st / last 50 feet Pave 000 P Required Open Section SS & FF feet - 0 days SS & FF feet - 0 days of Highway R Move Machine Type of restraint P=physical, R=resource and reason for restraint and duration between activities Pave Next Location Check for: physical open ends duplicative resource logic What if: add crews/equip/forms? add falsework/relax code?

15 Reason/Why Codes Special reason why codes physical just-in-time or subordinate support calculate latest dates to not delay early start of successor to restraint Survey P Excavate P Fdn P P P Fdn Fdn Rig & Set J = Just-in-Time P P P P Procure Submit Approve Fabricate Deliver

16 Additional code data on restraints Just-in-Time Physical Restraint distinguish prevent delaying project / prevent delaying work crew calculate new attributes JLS, JLF, JTF Rig/Set Steel is Critical Equipment has float Legend Top Line (Green) is Early Dates, Middle Line (Yellow) is Junior Dates, Bottom Line (Purple) is Late Dates

17 Just-in-Time Date & Float Attribute Legend Top Line (Green) is Early Dates, Middle Line (Yellow) is Junior Dates, Bottom Line (Purple) is Late Dates

18 Relationship Codes Restraint v Relationship Codes resource codes user defined activity codes Calculation on the fly? conduit cable connections energize rig pump pipe to pump run wire to pump Highlight the Handoff mechanical to electrical subcontractor crew movement between job area locations is there a handoff or demob/remob duration?

19 Put it all together event codes & text duration codes reason/why codes & text expanded lead/lag codes relationship codes 440i 440 Main Bldg - Install Roofing 0 C R RF A S3 440i0 at 500 SY of 5000 SY Crew Roofers FS RF Physical -- FS 0 -- Physical Penetrations at 50% PS 50% 440i 450i 40i Building Watertight 440 Garage Install Roofing 5 C R RF A5 S3 450 Main Bldg Studs & Drywall 0 I M 4 CP S0 S07 40 Main Bldg Roof HVAC 4 I M 4 SM S3 M4

20 Notice to Proceed Foundation Excavation Cure 0 5 Cure ADM Cure Cure Foundation Backfill Notice to Proceed 0 Foundation Excavation 5 FS PDM FS FS FS Foundation Backfill Notice to Proceed Foundation Excavation CP Crew 3 Rod Crew Cure FS Conc Crew Labor Crew Physical RDM Physical Physical 5 8 s # CP Crew Rod Crew 3 Cure FS Conc Crew Cure FS Labor Crew Physical Physical s # CP Crew Rod Crew Conc Crew Labor Crew Physical Cure FS Foundation Backfill 3

21 Industry Adoption

22 RDM is now in Primavera s Pertmaster v8.

23 Hailey Burton Cartwright Construction Company v. Macaw Casino Company

24 what s new on the screen? restraints have different colors two late start/finish bars reference to link category reference to ignore link

25 Reason/Why Codes Steel required before elev floor slabs

26 Relationship Codes

Relationship Codes A 0 - SiteG0 Notice to Proceed B 000 - SiteG0 Mobilize C fs D No LINKTYPE 0 LINKTITLE 0[fs] 000 G H I J K ACT 0 SUC 000 ACRTY SCRTY ALOC S SLOC S ALOC G0 SLOC G0 unknown craft

SCRTY CP ALOC W SLOC W ALOC 0 SLOC 09 EDIT <C:> TRIAL07P Rec: 5/08 A 5 - WestGS Erect, Bolt, Plumb Steel to Elev 77 B 0 - WestCL / Slab @ Casino Level C fs D No LINKTYPE LINKTITLE 5[fs] 0 G H I J K

27 Relationship Codes A 0 - SiteG0 Notice to Proceed B SiteG0 Mobilize C fs D No LINKTYPE 0 LINKTITLE 0[fs] 000 G H I J K ACT 0 SUC 000 ACRTY SCRTY ALOC S SLOC S ALOC G0 SLOC G0 unknown craft unknown reason/why EDIT <C:> TRIAL07P Rec: /08 A 30 - West0 / Elev 7 B West09 / Slab C fs D No LINKTYPE 3 LINKTITLE 30[fs] 300 G H I J K ACT 30 SUC 300 ACRTY CP same crew different floor SCRTY CP ALOC W SLOC W ALOC 0 SLOC 09 EDIT <C:> TRIAL07P Rec: 5/08 A 5 - WestGS Erect, Bolt, Plumb Steel to Elev 77 B 0 - WestCL / Casino Level C fs D No LINKTYPE LINKTITLE 5[fs] 0 G H I J K ACT 5 SUC 0 ACRTY IW SCRTY CP change craft physical reason/why ALOC W SLOC W ALOC GS SLOC CL EDIT <C:> TRIAL07P Rec: 7/08 A 0 - WestGS / Footers B 0 - EastGS / Footers C fs D No LINKTYPE 4 LINKTITLE 0[fs] 0 G H I J K ACT 0 SUC 0 ACRTY CP SCRTY CP ALOC W SLOC E ALOC GS SLOC GS same crew different building EDIT <C:> TRIAL07P Rec: /08

28 Who asked for RDM?

29 Who asked for RDM? You Did!!! 59

30 Just-in-Time Date & Float Attribute As Early as Possible As Late as Possible w/o delay to Project As Late as Possible w/o delay to Production Just In Time LinkType

0± D 0± C 0± Project Duration 3⅔ % 9 00 8 90 7 80 5 4 70 3 0 % 0 50 9 40 8 7 30 5 0 4

MC Sheet of Excerpt from page 4 of CPM in Construction Management EXPECTED DATE 3 MAY

31 How accurate is the CPM calculation? Risk and Monte Carlo Simulation A 0± B 0± C 0± D 0± 40 Estimating A 0± Scheduling B 0± D 0± C 0± Project Duration 3⅔ % % DAY LATEST DATE 5 JUN MC0MPRJ.MC Sheet of Excerpt from page 4 of CPM in Construction Management EXPECTED DATE 3 MAY EARLIEST DATE MAY TARGET DATE 30 MAY 0 Plot Date 0FEB0 (c) Primavera Systems, Inc. MONTE CARLO TEST # Title Finish Date of Project Date Revision Checked Approved

32 Risk Analysis Features of Pertmaster v8.5

33 Risk Analysis 000 Iterations

34 Risk Analysis 000 Iterations

35 Risk Analysis with RDM 000 Iterations

36 Risk Analysis with RDM 000 Iterations

37 Better Specifications CPM is a Shop Drawing Purpose = Further Assurances Owner does not want CPM to show timely completion Owner wants CPM to assure timely completion Contractor shall provide a CPM: that indicates an 80% likelihood of completion on or before June 30, 009 prepared in the RDM format to separately show physical planning restraints from resource scheduling restraints coded to indicate sub, craft, location Updates to the CPM shall include additional reports that incorporate: trend analysis starting at 30% for any classification of work or subcontractor dynamic re-leveling with up to 5% additional resources if the likelihood of timely project completion falls below 80% a cost analysis if resources are to be increased involuntarily beyond 5%

38 The Road Ahead

39 Reason/Why Codes Special reason why codes resource leveling must suppress (ignore) R reason coded restraints for same resource R code temporarily replaced with S code for reporting and analysis L code restraints track actual resource deployment by leveling routine L coded restraints are deleted each time the leveling routine is re-run

40 Trend Durations for ACTIVITIES based upon any common resource based upon any user defined activity code for progress style RESTRAINTS based upon reference activity for passage style RESTRAINTS based upon any common resource based upon any user defined restraint code

41 Split Activities Distinguish Passage v Progress Activity A 0 days Activity B 5 days versus 3 days 3 days Activity A 0 days Activity B 5 days

42 Split Activity Mimics SS v PS

Wallpaper days after starting Plaster Walls, and

43 Split Activity Mimics SS v PS SS PS event between split activities distinguishes start Wall A Wallpaper days after starting Plaster Walls, and start Wall A Wallpaper when days of Plaster Walls completed (Wall A)

44 Relationship Diagramming Critical Path Method CT Contiguous representing a Finish-to-Start restraint where the preceding activity may not start until a contiguous and continuous flow of work may occur from the start of the predecessor to the finish of the successor The lag portion of this Lead/Lag code represents the longest weekend permitted between activities The use of this restraint code will be similar to assigning a Zero Free Float constraint to the predecessor affecting the successor activity of THIS restraint only Activity A Activity B

45 Relationship Diagramming Critical Path Method CC Concurrent representing the two activities must be performed in lock-step this is more than saying two activities joined with SS+FF or PS+FR

46 Relationship Diagramming Critical Path Method CC Concurrent representing the two activities must be performed in lock-step this is more than saying two activities joined with SS+FF or PS+FR Examples include: erecting a MSE wall and backfilling during placement pouring a concrete slab with embedded electrical conduit coordination of surgeon and anesthesiologist during an operation in each instance possibly being performed by separate subcontractors but under the daily control of only one individual the proper logical means to depict the combination is by only one activity, however the needs for separate rollups by subcontractors and the general desire for such a splitting of this ONE activity indicate a need for this type of restraint code

47 Relationship Diagramming Critical Path Method DS Duplicate SS+FF restraints sharing the same lag duration the MSCS program of the 90s and 970s included a popular Z code = combination of SS+FF indicates that the early (but not necessarily the late) start of the two activities would start together or that the two activities (if having the same duration) would be staggered note predecessor and successor activities should have the same duration and calendar An error code should be generated for violations. DP Duplicate PS+FR restraints sharing the same lag duration Similar to the DS restraint, except the successor activity will be calculated to start after the remaining duration of the predecessor has been reduced by Lag units of time. DR Duplicate RS+FP restraints sharing the same lag duration Similar to the DS restraint, except the successor activity will be calculated to finish after the remaining duration of the predecessor has been reduced to Lag units of time.

48 Other Contributions

49 performance of projects is measured by activities performance of projects is driven by relationships

50 Q&A

Working in Unexplored Territory. Technology, Project Delivery & Sustainable Design: Liability and Emerging Standards of Practice

Working in Unexplored Territory Technology, Project Delivery & Sustainable Design: Liability and Emerging Standards of Practice Introducing Fredric L. Plotnick, PhD., Esq., P.E. Moderator Co-Author CPM