MANAGING CONSTRUCTION SCHEDULES. Kelly Selman, P.E. Dallas District. Date. Dallas District October 10, 2017

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1 MANAGING CONSTRUCTION SCHEDULES Kelly Selman, P.E. Dallas District Dallas District October 10, 2017 Date

2 Types of Schedules Contract Time Schedule A+B Bidding Lane Rental Preliminary Schedule Project Baseline Schedule Progress Update Schedule Time Impact Analysis Dallas District October 10,

3 FHWA Definition: Importance of Contract Time Schedule Contract time is the maximum time allowed in the contract for completion of all work contained in the contract documents When Contract Time is Too short Impacts on bid prices from inefficiency to schedule resources, procure materials, etc. When Contract Time is Too long Inconvenience to the traveling public from construction activities taking forever Dallas District October 10,

4 8.3 Computation of Contract Time for Completion The number of working days is established by the Contract. For Contracts with work orders, the number of working days is established in each work order. Working day charges will begin when work begins as prescribed in Article 8.1., Prosecution of Work. Working day charges will continue in accordance with the Contract. Upon request, the Engineer will provide the conceptual time determination schedule to the Contractor for informational purposes only. The schedule assumes generic resources, production rates, sequences of construction and average weather conditions based on historic data. The Department will not adjust the number of working days and milestones, if any, due to differences in opinion regarding any assumptions made in the preparation of the schedule or for errors, omissions, or discrepancies found in the Department s conceptual time determination schedule. Dallas District October 10,

5 Contract Time Determination (CTD) Guidelines Based on full evaluation of all factors involved: Complexity of the project Typical contractor organization likely to bid on the project Sequence of construction Traffic impacts Local field and weather conditions Overriding factor: Project completion urgency Dallas District October 10,

6 Essential Elements of a CTD Schedule Scope of work Identify the scope of work for scheduling needs Establish production rates Standard rates of production activities Adaption of rates for specific projects Establishing constraints Procurement / fabrication of long lead items Needs of the adjacent businesses / communities that will impact the work Restrictions on nighttime work High profile events Sequencing work to avoid obstacles (utilities, oil wells) Dallas District October 10,

7 Essential Elements of a CTD Schedule (cont.) Impacts of lane-closure restrictions on scheduling and logic Calendars Allow contractors flexibility to work 6 days Seasonal limitations Weather, temperature, daylight hours, etc. Letting month, start of the construction activities Affects from adjacent projects Third party construction projects, i.e., city projects Dallas District October 10,

8 Minimizing Impacts on Traffic: Lane Rental Fees for Lane Closures Use lane rental fees and liquidated damages for lane closures on construction projects as appropriate Establish Time periods in the contract for different volumes of traffic Time Period A = Peak hours of traffic Time Period B = Midday volumes Time Period C/D = Lowest traffic volumes (typically overnight or weekends) Time Period A lane closures are not allowed, but a dollar value is assigned in the event that an overnight lane closure is not picked up on time. These do not come out of the bank balance, but are deducted monthly from the estimate as liquidated damages. Dallas District October 10,

9 Dallas Horseshoe Project Lane Rental Fee Charges: Dallas District October 10,

10 Minimizing Impacts on Traffic - Lane Rental Fees for Lane Closures Dallas Horseshoe Project Example: Full westbound I-30 closure from 11pm Friday to 8am Saturday (9 Hours): 9 hours of Time Period C 9 x $5,048 = $45,432 Full northbound I-35E closure from 10pm Friday to 6am Saturday (8 Hours): 3 hours of Time Period C 5 hours of Time Period D (3 x $5,048) + (5 x $2,019) = $25,239 Total lane rental fees deducted from the bank balance = $70,671 Dallas District October 10,

11 Minimizing Impacts on Traffic - Lane Rental Fees for Lane Closures Dallas Horseshoe Project: Work Accomplished in 8 / 9 Hours: Set 7 Tx62 girders over westbound I-30 Set 8 Tx62 girders over northbound I-35E Placed temporary shoring and work platforms Removed bridge overhangs Removed existing high mast illumination pole Placed 1000 lf of portable concrete barrier Enhanced work volume from lane closures Dallas District October 10,

12 Dallas Horseshoe Project Example Lane Rental Fee Charges: Work Completed that evening: Dallas District October 10,

13 Dallas Horseshoe Project Dallas District October 10,

14 Multiple Crews Mobilized During a Freeway Closure Dallas District October 10,

15 A + B Bidding: Dallas Experience Summary - DAL A+B Projects Eng. Estimate Winning Bid Letting Year County Job # CCSJ # Daily RUC $ For 3 out of 4 contracts, the A part of the bid was under the Engineer s cost estimate For 4 out of 4 contracts, the B part was under the Engineer s duration estimate Competitive bidding yields optimization of cost + time savings # of Bids A (Bid Items $) Time Estimate (Days) A+B encourages potential bidders to develop carefully developed execution plans for achieving cost-time optimization B (Days DRUC $) A (Bid Items $) The road users and the traveling public benefit from both time and cost savings % O/U (A) Time Estimate (Days) % O/U (B) Jan Ellis $3,300 7 $71,229, Days $2,409,000 $61,704,500-13% 687 Days -6% May Dallas $20, $59,686, Days $14,040,000 $59,011,998-1% 468 Days -33% Jun Dallas $50,000 5 $72,032, Days $39,000,000 $78,786,039 9% 618 Days -14% Jul Denton $4,000 7 $36,799, Days $2,760,000 $35,041,150-5% 650 Days -6% Dallas District October 10,

16 Baseline Schedule The Contractor s Plan of Work Prepared by the Contractor and reviewed by TxDOT staff for compliance Must include all contract work Must follow the Traffic Control Plan Must have proper calendars including added weather days, holidays, etc. Clear and logical critical path / longest path Long lead / Fabricated items included Use the full number of contract days A+B resolves issues with contract days Dallas District October 10,

17 Monthly Schedule Updates Follows the approved Baseline Schedule Ensures the schedule is updated to show all work that has been completed Calendars updated to show actual days worked Review logic changes Did they affect the Critical Path? Use of Constraints Is the schedule overly constrained? Dallas District October 10,

18 Schedule Review Checklist for Dallas District Dallas District Review Checklist for Monthly CPM Schedule Updates CSJ: Schedule Name: IH-35E (Denton)-08 Highway: IH 35E Data Date: 8/31/2017 County: Denton Reviewer: Tom Smith Contractor: ABC Contractor Review Date: 9/26/2017 Yes No N/A Item Comments Is the schedule a separate file from the original detailed (baseline) schedule file (or any other previous schedule files)? Is the schedule calculated using retained logic? Is there a hammock activity to calculate contract time and is it associated with a calendar that accurately reflects how time will be charged? If the schedule shows a change in TCP, has a formal request letter been submitted? If the schedule is a "revision" as defined in the specifications, has a written request by the Contractor been submitted non-work and approved? Are calendars set up logically, and do they consider non-work holidays and weather? Do activities use appropriate calendars? Have the calendars been updated to reflect actual days worked/not worked? Are activities properly coded and/or can the schedule be organized logically using the coding structure? Have resources been updated to reflect actual conditions and is resource loading fully implemented? Is/are the critical path(s) clearly discernable and accurately identified? Is the use of constraints kept to a minimum and is there no imposed finish date? Other than start and finish activities, do all activities have predecessors and successors? See attached comment #1 Are there no new/deleted activities? (if no, list) See attached comment #2 If there are new/deleted activities, are they justifiable? If there are any new activities, have the appropriate calendars, activity codes, and resources been associated? Have the relationships been edited accordingly? Do the actual start and actual finish dates correspond with the dates the work was performed in the field? (especially for critical activities in this schedule or previous schedules) See attached comment #3 Are the percentages complete calculated using the given production rates? If there is any out of sequence work, is it acceptable? See attached comment #4 Has there been no gain/loss in time since the last schedule update (use PSSR form; investigate and document the cause for any gain/loss)? See attached comment #5 Has Claim Digger been used to compare this schedule with previous updates? See attached comment #6 Are there no other concerns with the schedule? Dallas District October 10,

19 Schedule Review Project Schedule Status Report Project: STP 2017(083) MM CSJ: Exhibit "B" Project Schedule Status Report County: Denton Contractor: ABC Contractor Schedule Name Contract Days: 442 Data Date Completion Date Working Days Rem Duration Percent Complete Workweek: 6 Day Calendar Days Working Days Days Granted by TxDOT Period Gain/Loss Cumulative Gain/Loss Period Gain/Loss Cumulative Gain/Loss Calendar Days Working Days Explanation for Loss/Gain Feb-17 1-Aug Baseline Schedule Submittal (Not approved) Mar Aug Baseline (Rev 2) Schedule Submittal (Approved) Apr Dec % IH35E May Dec % IH-35E (Denton) Jun Dec % IH-35E (Denton) Jul Jan % IH-35E (Denton) Aug Feb % The project lost 89 workdays due to the delay in pipe delivery for the waterline, added activities, and the change in schedule logic by the contractor in which the Phase 1 Step 1 SB Frontage Roadwork could not begin until the waterline was installed. No Change this update period. The project gained 13 workdays due to the contractor beginning to install the new water line sooner than previously planned last update period. The project lost 36 workdays due to the procurement of the new water line valves. The project lost a total 26 workdays this update perior due to the 1) lack of progress on the new water line - 8 days; 2) the contractor making schedule logic changes to the water line installation - 13 days; and 3) the contractor adding a new water line installation activity (Activity No. A Install Water System Sta New Water System) - 5 days. Schedule Name: The unique filename assigned to the original schedule, updates and revisions. Data Date: The calendar date when the project has been updated and the network revised, statussed or progressed. Completion Date: The unconstrained, unrestricted calculated project completion date as calculated by Primavera Project Planner (P6). Working Days: Calculated by P6 using a hammock activity and with an updated calendar reflecting actual time charges. Period Loss/Gain: The number of calendar days or working days the project completion date has been delayed (positive figures) or accelerated in current period. Cumulative Loss/Gain: The total number of calendar days or working days the project completion date has been delayed or accelerated since the original schedule. Days Granted by TxDOT: Enter the contract days added by Change Order. Dallas District October 10,

20 Time Impacts Analysis Contractor submits a Notice of Potential Impact and utilizes the 4-Step process Step 1 Establish the Status of the project before the impact. Step 2 Predict the effect of the impact on the schedule. Step 3 Track the effects of the impact on the schedule Step 4 Establish the status of the project after the impact. All four steps must be completed to analyze the impact on the project. Dallas District October 10,

21 Summary Scheduling is a tool to help achieve project objectives and meet the public s expectations for timely project delivery Ensure accurate documentation of project progress Engagement of the AO and District staff in: Developing/reviewing contract time schedules Reviewing Baseline schedules Reviewing progress update schedules Dallas District October 10,