MDCSystems. Measuring Extent and Responsibility for Delay Scheduling. presented by Robert C. McCue, P.E. President.

Transcription

1 MDCSystems Providing Expert Solutions for Construction Worldwide Measuring Extent and Responsibility for Delay Scheduling presented by Robert C. McCue, P.E. President

2 Schedule Development and Implementation Contract should specify: What the schedule should show Notice to Proceed Milestones Substantial Completion

3 Elements of all Schedules Milestones Notice to Proceed Phasing requirements Testing/Acceptance Operational date Beneficial use Substantial completion

4 Key Activities/Interfaces Work of other contractors Long lead time materials/equipment Owner furnished material/equipment Phasing requirements

5 Basic Schedule Development Steps Activities from the WBS Alternative-Drawings and specifications Activity duration from experience/calculation Logic from experience/planning Start/Stop dates from requirements/phasing Concurrent activities from experience/interface requirements

6 Schedule Formats Bar Chart Schedules (Gantt Chart) PERT Chart Schedules Network Diagram Schedules Precedence Method Schedules Critical Path Method Schedules

7 Bar Chart Schedules (Gantt Chart) GANTT CHART Production Schedule No. Unit 2501 Work Weeks

8 Bar Chart Schedules (Gantt Chart) Strengths Most common schedule Common sense logic Quick determination of gross progress Simplicity

9 Bar Chart Schedules (Gantt Chart) Weaknesses Logic not shown No critical path Difficult to determine overall project status Does not help establish relative sensitivity

10 PERT Chart Schedules Special te=3 component study B te = 5 Vendor evaluation E te = 8 PERT Network Showing precedence of activities (tasks) A te = 2 Layouts C te = 4.5 Subcontract specifications Subcontract liaison G Time estimates for each activity 1. Optimistic 2. Most likely 3. Pessimistic Expected time = te te=4.5 Subsystem design D te = 8 Subsystem tests te = 7 Final drawings F = Planned event = Critical Path (longest path) = Activity

11 PERT Chart Schedules Strengths Responds to interrelationships between activities Produces Best Guess completion estimate Commonly used on projects which have no historical information to base activity duration estimates

12 PERT Chart Schedules Weaknesses Input can be complex and time consuming Updating can be onerous Does not identify the project critical path

13 Network Diagram Schedules

14 Network Diagram Schedules Strengths Automatically accounts fro uneven activity durations Incorporates resource requirements such as manpower, material, equipment, money, etc. Identifies which portions of a project have float time and are not driving the overall time to complete the project.

15 Network Diagram Schedules Weaknesses Input can be complex and time consuming Updating can be onerous Results are only as good as the input. Logic flaws can be hidden and yield faulty projections. Pure logic diagrams can be very hard to read and understand.

16 Precedence Method Schedules CAMOUFLAGE PRINTED NYLON COTTON MATERIAL TESTING WOVEN GREIGE GOODS OC TEST PRINTING & FINISHING CUT CUT PARTS OC MATERIAL TESTING

17 Precedence Method Schedules Strengths Does show inter-activity relationships and constraints Forces consideration of preceding / succeeding activities.

18 Precedence Method Schedules Weaknesses Input can be complex and time consuming Updating can be onerous Results are only as good as the input. Logic flaws can be hidden and yield faulty projections.

19 Critical Path Method Schedules Critical Path Network E L B D F N A O C G I H J M K Legend Event number - Critical Path - Activity arrow - Dummy arrow -

20 Critical Path Method Schedule s (CPM) Strengths Time scaled logic shown Logical graphic display Facilitates alternative planning Displays critical path Computer generated sorts of key data Quick summary and milestone plots Relative ease of resource loading

21 Critical Path Method Schedule (CPM) Weaknesses Computer required Tedious data entry Complex calculations of time requirements Logic blocks to quick schedule revisions Must be maintained

22 Schedule Check Points Does the schedule conform to contract dates? Milestones indicated? Is phasing currently shown? Logical sequence of activities? Activity durations are reasonable? Do resources allocations seem reasonable? Interface work is indicated? Is testing indicated? Critical path indicated? Progress shown?

23 Schedule Analysis Techniques Global Impact Approach Net Impact Approach Adjusted As-Planned CPM Approach Adjusted As-Built CPM Approach Collapsed As-Built Schedule Approach Impacted Updated CPM Approach Modification Impact Analysis Time Impact Analysis(TIA)

24 Global Impact Approach Simplistic All delays on an as-built bar chart Duration of each delay event is totaled Total delays is the sum of all delaying events Does not show concurrency Time extension beyond actual projection completion

25 Net Impact Approach All delays on an as-built bar chart Change Orders are delays Time extensions is difference between asplanned completion and actual completion Individual delay impacts are not calculated Relationship analysis is not possible

26 Adjusted As-Planned CPM Approach Delay events are activities or restraints Delays entered without regard to actual progress The original plan may have been unworkable Delays may have changed the critical path

27 Adjusted As-Built CPM Approach Delay events are activities or restraints Delay events are tied to claimants Critical Path

28 Collapsed As-Built Schedule Approach Variation of the adjusted as-built schedule approach Applies But-For logic Claimants negligible delays are left out Significant cause and effect relationships are not given proper consideration Relies upon hypothetical of What could have happened?

29 Impacted Updated CPM Approach Impacts the approved updated schedule Often updated during the course of construction Scope of changed work is reviewed to determine schedule revisions Contractor entitled to time extension only if delayed beyond project completion date Implies that the project schedule is correct, as updated

30 Modification Impact Analysis Approach Determines the actual status of the job when the delay occurred Delay causing event studied to determine subsequent activities affected New calculations determine critical path, revised completion date and time extensions for the delay Adjustments should be done at or near the time of the delay-causing event

31 Time Impact Analysis (TIA) Isolates and quantifies impact of individual delay causing events Uses both as-planned and as-built schedules Identifies a day-for-day increase to project date

32 Update and Schedule Analysis Techniques Compare schedule data with asbuilt/completed project history Use independent data sources for verification Logs Pictures/Video Progress reports Compare planned vs. actual durations Similar activities Work in progress

33 Schedule Analysis Techniques Perform schedule update Depict actual status Make projections using existing schedule Logic and durations Determine the predicted end date

34 Schedule Analysis Techniques Reschedule activities and durations to adjust end date Develop fragnets (mini- networks) Revise logic to respond to events and progress What-if scenario Revise activity durations Apply parametric techniques Reapply resources to activities Publish revised best fit schedules

35 Remember Schedule development and re-planning is an art as well as science If you feed a computer garbage data it will produce garbage schedules Apply common sense/parametric thinking to analyze computer output Good schedules and honest analysis = good project management

36 Common Problems that Affect Schedule Differing conditions Access to site Availability of site Technology development Active interference Disruption Review and approval process Work sequence Weather

37 More Interferences Changes Delay Materials Constructive acceleration Directed acceleration Impossibility of performance Superior knowledge Technical error Defective plans and/or specifications

38 Delay Excusable Non-excusable Compensable Non compensable Critical Concurrent

39 Acceleration Directed Constructive

40 Disruption Start/Stop iteration Trade stacking Over-manning Environment/Weather

41 Blake Construction Co. vs. C.G. Cookby, Inc. Except in the middle of a battlefield, nowhere must men coordinate the movement of other men and all materials in the midst of such chaos and with such limited certainty of present facts and future occurrences as in a huge construction project.

42 The Construction Project First story-public space Stories 2-8 tenant Stories 9-15 court Total project cost $91 Million Construction cost $79 Million Project consists of +/- 300,000 sq. ft. of office space and underground parking Design-Build

43 The Beginning Owner expectations Plans and specifications reasonably complete Design consistent with objectives/concepts Contractor takes into consideration all events Reality No plans perfect Unexpected events occur

44 Contract Work clause The construction and services required by Contract Documents Includes all labor, materials, equipment and services to fulfill Contractor s obligations Owner needs to define work as broadly as possible Consider work inferred by the contract documents

45 Change History Soil contamination Late structural design Late tenant build out design

46 Soil Contamination Contractor ran into unforeseen conditions soon after beginning construction All site work stopped for four months Contractor sought 120 calendar day time extension Owner granted 90 time extension plus money Owner refused to acknowledge the actual impact associated with a changed condition and change order

47 Soil Contamination Owner and contractor need to conduct investigations Owner should consider providing data from site investigation Makes it easier for owner to see if project feasible

48 Site Investigation Clauses Owner should require Consider requirement of subsurface samplings vs. a simple reasonable investigation

49 Soil Contamination Delay Claim Chemical contamination of soil NTP March 18, 1994 Excavation work stopped June 13, 1994 Owner & Associates negotiation right to stop work if site materials hazardous Request: 125 contract days & $4,007,000 CO: 90 cd & $1,799,000

50 Owner s View of Soil Issues ABC had begun on-site activities later than As-Planned Schedule Had the contractor discovered the soil conditions earlier, less of an extension required ABC contends misconception by Owner Actual critical delay of 120 cd caused solely by soil conditions 120 cd remained a part of Baseline Schedule ABC had to accelerate work on excavation and foundation by 34 cd to absorb loss of 30 cd

51 Soil Contamination Timeline

52 Time Impact Analysis(TIA)

53 Structural Steel Delay Contract called for contractor to provide high load structural steel. (10% of tenant areas) Owner delayed identification of specific areas requiring high load steel Contractor could not pour concrete or perform other tasks including fabricating and erecting steel Critical delay of 64 days to start steel erection To mitigate impact of late start of steel erection, contractor re-sequenced other work and accelerates the start of curtain wall installation

54 Structural Design Issues Late decisions by owner resulted in late completion of the structural design by MMJ Design revised due to tenant changes 422 tons of steel added, increase of 10% of ABC s BAFO Design revisions had major impact on structural steel detailing by 123 Steel Critical delay of 64 cd to start steel erection

55 Actions to Mitigate by ABC To expedite project and mitigate delay ABC provided COs to 123 Steel: CO #2 to accelerate shop detailing and fabrication of steel CO #3 for scope changes and acceleration to the erection of steel Commenced steel erection without signed easements proceeded at risk Re-sequenced installation of curtain wall to start before completion of steel erection Effect: took steel off critical path, making pre-cast erection the critical path Saved six days

56 Structural Steel Timeline

57 Time Impact Analysis(TIA)

58 Tenant Work/Finishes Tenant space bid as raw space Contract included unit prices for items Owner believed would be utilized Contractor included $8 million for tenant space Work requested by tenants was estimated by contractor to cost $13 million Took owner almost a year (329 days) to procure the additional $5 million dollars and finalize tenant build-out plans Critical project delay of 137 days in addition to previous delays

59 Interior Finish Initially courtroom and judges chambers interior finish work on critical path Delay in erection of curtain wall system Building not weather tight Build studs and rough plumbing Lack of info from Owner on security system Delayed custom door frames Delayed sheetrock, millwork and finishes

60 Tenant Work/Finishes Timeline

61 Time Impact Analysis(TIA) Snapshot technique Goal is to develop an analytical model to isolate and quantify impact of individual delay-causing events through an examination of the status of project at certain times Stop-action picture of project Each time major impact in schedule Status dates Uses both as-planned and as-built schedules May involve several updates and revisions of project schedule What shown? Day-for-day increase to project completion date Available float consumed until fragnet path becomes critical Only available float consumed Event may be concurrent with another delay Time may be recovered by accelerating work or re-sequencing

62 Time Impact Analysis(TIA)

63 Time Impact Analysis(TIA)

64 Overall Project Analysis by MDC Total delay of 329 cd to project completion 174 net cd delay in project completion 148 cd of delay avoided by mitigation efforts by developer 84 cd acceleration costs recoverable Entitlement to excusable and compensable extensions of time that amount to 174 days Entitled to recover acceleration costs for 84 days

65 Eichleay Formula for calculating unabsorbed overhead costs in connection with governmentcaused delay to public construction projects will be applied only if the contractor establishes two things: that it was on "stand by," and not working on the project, but nevertheless bound to it, and that it was unable to take on substitute work while on stand by. Complete General Construction Company v. Ohio Department of Transportation, 94 Ohio St. 3rd 53, 760 NW 2nd 364 (2002).

66 Recovery under the Eichleay Formula is intended to compensate a government contractor for "unabsorbed overhead costs" that accrue when completion of the contract required more time than originally anticipated on account of a delay caused by the government. Nicon Inc. v. United States, 51 Fed Cl. 324 (2001). Interestingly, in a recent decision, the armed services board of contract appeals held that while a contractor must prove that it went into stand by mode in order to recover unabsorbed office overhead, it need not be alleged in the pleadings. Appeal of DCO Construction, Inc. v. NSBCA No., 5701 May 2, 2002)

67 Contact Us! MDCSystems 300 Berwyn Park Suite 115 Berwyn, PA