Construction delays chapter eight delay analysis using no schedules

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Construction delays chapter eight   delay analysis using no schedules

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Construction delays chapter eight delay analysis using no schedules Construction delays chapter eight delay analysis using no schedules Construction delays chapter eight delay analysis using no schedules Construction delays chapter eight delay analysis using no schedules Construction delays chapter eight delay analysis using no schedules Construction delays chapter eight delay analysis using no schedules Construction delays chapter eight delay analysis using no schedules Construction delays chapter eight delay analysis using no schedules

CHAPTER EIGHT Delay Analysis Using No Schedules USE OF CONTEMPORANEOUS DOCUMENTS FOR SEQUENCE AND TIMING The preceding chapters discussed the performance of a delay analysis using a detailed Critical Path Method schedule and a bar chart This chapter addresses the “worst case” situation: the project with no asplanned schedule or schedule updates This is the most difficult situation in which to perform a delay analysis Again, as the available information decreases, the analyst must make more assumptions, and the analysis becomes more subjective However, while this type of analysis is difficult, it is not impossible When there is no schedule upon which to base an analysis of delays, it is usually because no schedule was prepared Alternatively, it may be that a schedule was prepared, but the schedule was so flawed that it could not serve as the basis for a reliable analysis of delays With regard to this latter circumstance, keep in mind that perfection is not the standard when determining whether a schedule can be used to analyze delays No schedule is perfect and it is the rare project that is built exactly as scheduled The analytical approaches discussed in Chapter 7, Delay Analysis Using Critical Path Method Schedules, are often self-correcting when it comes to schedule errors Consequently, the existence of errors is not reason enough to abandon the use of the project schedules to evaluate project delays The rejection of an available schedule as the basis of analysis is discussed at greater length in preceding chapters of this book Regardless of the reason why a schedule is not available to analyze project delays, the approach to analyzing delays without a schedule is essentially the same The first step to performing an analysis without schedules is to review the project document files to identify anything that might serve as a basis for determining how the parties planned to execute the project There Construction Delays DOI: http://dx.doi.org/10.1016/B978-0-12-811244-1.00008-2 Copyright © 2018 Trauner Consulting Services, Inc Published by Elsevier Inc All rights reserved 203 204 Construction Delays are many potential sources, but the following is a useful guide for identifying the documents most likely to provide as-planned information regarding the planned sequence of the work or timing for the project work activities The analyst should review the following: • The contract documents for any specific required sequencing, phasing, or staging for the project work (Fig 8.1) • Correspondence between the general contractor and the owner or owner’s representative for references to sequencing or timing, even if only for a portion of the project (Figs 8.2 and 8.3) • Subcontract agreements to look for any sequencing or timing dictated to the subcontractors by the general contractor concerning subcontract work • Correspondence with subcontractors for any discussion concerning scheduling, sequencing, or timing (Fig 8.4) Figure 8.1 Example contract language specifying work sequence Figure 8.2 June 15, 2007 contractor correspondence Delay Analysis Using No Schedules 205 Figure 8.3 August 20, 2007 owner correspondence Figure 8.4 June 25, 2007 contractor correspondence to subcontractor • • • Partial schedules produced during the project, which may describe the planned sequencing or timing for portions of the project (Fig 8.5) Meeting minutes of any discussions concerning scheduling, particularly the preconstruction meeting minutes (Fig 8.6) Daily log or diary entries by either the general contractor’s personnel or the owner’s representative (Fig 8.7) 206 Construction Delays Figure 8.5 Partial schedule, 10-week look-ahead Figure 8.6 Preconstruction meeting minute excerpt • Purchase orders with suppliers that show planned dates for delivery of materials or equipment The analyst should use all the available project information to define some form of an as-planned schedule or at least to establish a general planned sequence for the work on the project for different parts or portions of the project Based on the sample information provided in Figs 8.1À8.7, the analyst is unable to determine an as-planned schedule However, the following information can be determined: The contract required that all abutment work be completed before any paving was performed on the approaches The contract also required that completion of the project occur by the middle of the 24th week (from Fig 8.1) Delay Analysis Using No Schedules 207 Figure 8.7 Daily diary excerpt The contractor planned to work from east to west, or from Abutment #1 to Abutment #2, and from Pier #1 to Pier #3 (from Fig 8.2) The owner’s representative noted that the review and approval of the shop drawings for the reinforcing steel in the pier caps had taken longer than required and were not returned to the contractor until weeks later than requested (from Fig 8.3) The contractor planned on erecting the steel at the beginning of the 13th week of the project (from Fig 8.4) The contractor produced at least one, 10-week “look-ahead” schedule that addressed the work on the piers and described the specific sequence for this work, including the piles, pile caps, pier columns, and pier caps (from Fig 8.5) The contractor anticipated a 2-week duration for the forming, reinforcing, and placing of each of the concrete deck spans (from Fig 8.6) The contractor expected 4-week durations for each of the abutments and 2-week durations for each of the approaches (from Fig 8.7) Based on this information, the analyst can proceed with the analysis, despite the lack of a complete as-planned schedule Keep in mind that the goal is not to prepare an “alternative” or “after-the-fact” baseline or as-planned schedule for the project Rather, the goal is to mine the project information in search of the contractor’s original plan for construction While the analyst may be tempted to 208 Construction Delays create an after-the-fact schedule, reasoning that it will allow the analysis to be more precise, the opposite is true To the extent a “planned” schedule is drafted as the basis of the analysis, it should be done so with only the information that can be gleaned from project documents, such as the examples outlined in this chapter, along with mandatory sequencing dictated by the physical construction attributes and conditions More importantly, it should be used with the knowledge and understanding that it is incomplete and limited in terms of its precision USING AN AS-BUILT ANALYSIS TO QUANTIFY DELAYS For projects that have no planned or updated schedules, the daily reports may provide sufficient detail to allow for a reliable analysis of delays, especially when used in conjunction with the planned information gleaned from the project documents Daily reports allow the analyst to prepare an as-built diagram for the job The as-built diagram for the example project based on the daily reports is depicted in Fig 8.8 In reviewing the as-built diagram, it is evident that the project was delayed seven-and-one-half weeks It was to be completed by the middle of the 24th week, but was not actually completed until the end of the 31st week Therefore, the analyst must account for at least seven-andone-half weeks of net delay The delay could, in fact, be greater if the contractor had planned to finish the project early, or if the contractor was able to mitigate some previous delays However, there is no indication in the project documents to establish a plan to finish early The as-built diagram also shows that the contractor did work from east to west as planned Based on the letter to Ferrous Steel Erectors (Fig 8.4), the contractor planned to start steel erection at the beginning of the 13th week The asbuilt diagram (Fig 8.8) shows that steel erection began at the beginning of the 18th week A 5-week delay can be identified for the start of the steel erection Following this conclusion, we would break down the activities that precede the start of steel erection Using the 10-week “look-ahead” schedule from Fig 8.5, which the contractor produced at the end of the second week of the project, a comparison of this schedule with the asbuilt diagram for this portion of the project shows that a delay occurred Delay Analysis Using No Schedules 209 to the construction of the pier caps A delay also appears in the construction of Pier Column #3, which took weeks instead of weeks to complete The comparison of the partial “look-ahead” schedule with the asbuilt portion is shown in Fig 8.9 Figure 8.8 As-built diagram 210 Construction Delays Figure 8.9 Comparison of 10-week look-ahead and as-built diagram Based on this comparison, it appears that the initial critical delay was the delay to the start of the Pier Cap #1 This may have been the result of the 5-week delay in approval of the shop drawings to which the owner’s representative had referred in correspondence (Fig 8.2) It does not appear that the delay in the completion of Pier Column #3 affected the completion of the project, as the flow of activities in the “look-ahead” schedule (and in the logical construction sequence) would have been in the stair-step fashion depicted Delay Analysis Using No Schedules 211 The remainder of the work along the pier and deck path appears to have been performed in a logical, sequential fashion and does not indicate further delay However, there is a gap between the completion of the curbs and sidewalks and the beginning of the punch list work Based on the as-built diagram, the punch list work did not start until the abutments and approaches were completed The abutment and approach work occurred in the sequence planned However, it appears that the performance of the abutment and approach work delayed the project an additional two-and-one-half weeks, as this is the gap between the completion of the superstructure work and the start of the punch list work Based on the documentation available, it can be determined that the abutment and approach work started later than planned, but was performed within the duration planned by the contractor A summary of the delays appears in Fig 8.10 The delay of sevenand-one-half weeks is from: Five weeks of delay to the start of the pier cap work, from start of Week 7, when Pier Cap #1 should have started, to the start of Week 12, when Pier Cap #1 actually started Two-and-one-half weeks of project delay due to the 13-week late start of the abutment and approach work At this point in the analysis, the analyst should again carefully review the project documentation to determine if other supporting information is available to further substantiate the delay analysis Of particular interest in this case would be the need to confirm the assumption that the project delay is properly attributed to the late start of Pier Cap #1 and not the delayed start of abutment work For example, if the project documentation shows that the start of the abutment work was delayed because the owner failed to procure the needed permits to allow the abutment work to start and that the permits were not going to be received until Week 11 or later, then the permit delay may be the reason that the contractor waited to start the pier cap work until all three columns were completed In fact, doing so may have been prudent in that it avoided the mobilization of additional work barges that would have been necessary in the original plan Keep in mind that, in the original plan, the pier and deck work may have been critical, but once the permit was delayed to the point where the abutment and approach permit path was now the longest 212 Construction Delays Figure 8.10 Summary of delays path, each additional day of delay would add float to the pier and deck path Critical path shifts and the consumption and creation of float are discussed in detail in the previous chapters of this book Despite the lack of a planned schedule in this case, the project still has a dynamic critical path that must be considered ... portion of the project shows that a delay occurred Delay Analysis Using No Schedules 209 to the construction of the pier caps A delay also appears in the construction of Pier Column #3, which... partial “look-ahead” schedule with the asbuilt portion is shown in Fig 8.9 Figure 8.8 As-built diagram 210 Construction Delays Figure 8.9 Comparison of 10-week look-ahead and as-built diagram... permit was delayed to the point where the abutment and approach permit path was now the longest 212 Construction Delays Figure 8.10 Summary of delays path, each additional day of delay would

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  • Eight Delay Analysis Using No Schedules

    • Use of Contemporaneous Documents for Sequence and Timing

    • Using an As-Built Analysis to Quantify Delays

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