EA 08-472214

slide 1

Jonathan den Hartog, P.E.

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slide notes

• Introduce yourself.
• $52 million project pavement rehabilitation project
• Begun in April 2009. Estimated completion by the end of this year.

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slide 2

Project Location

slide notes

• Ontario is about 40 miles east of downtown LA
• In Addition: Major route for Las Vegas traffic. No break on weekends.

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slide 3

Project Location

slide notes

• Again, no break on weekends

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slide 4

Project Features

• Median Paving
• Bridge Widening
• New Median Barrier
• Shoulder/Ramp Rehab
• Pavement Rehabilitation
  • 12 ln-mi lane replacement
  • Random slab replacements
  • Includes connectors
  • Precast Pavement (Super-Slab)

slide notes

• Picture is non-rush hour, on a weekday. Saturday would be similar. All days can have traffic jams
• Bridge widening was to close the gap between NB and SB bridge decks.

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slide 5

Traffic Volumes

slide notes

None.

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slide 6

Construction Sequence

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None.

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slide 7

Rapid Weekends

• 5 Major Stages,
  • 25 sub-stages
• 410 Working Days (~2 yrs)
• 55-Hour Weekend Closures
  • Beginning late Friday evening
  • Ending early Monday morning
• Approximately 30 weekends
• ~8 full roadbed closures

slide notes

• Needed CA4PRS to justify this approach.
• Also, wanted to include incentive to reduce number of weekend closures. Needed to justify this.

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slide 8

Typical Closure

slide notes

None.

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slide 9

CA4PRS Study

• 2 Phase Study
  • Alternative Analysis And Comparison
  • Detailed Study of Preferred Alternative
• Performed by consultant sub

slide notes

• The subcontractor was Dr. E.B. Lee
• The CA4PRS study was done in conjunction with a traffic modeling study, performed by a different sub.
• At the time, CA4PRS did not include the Work-Zone Analysis or Agency Cost modules. These efforts had to be done separately.
  • Traffic analysis was done by EB Lee (in addition to the traffic modeling study) using the same Demand Capacity Model now incorporated into the software.

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slide 10

CA4PRS Study Purpose

• Validate the alternative chosen
• Provide a detailed estimate of:
  • Working days for the project
  • Number of closures needed for each stage
• Basis for Incentive/Disincentive

$150,000 per saved closure

(Max $900,000)

$175,000 per extra closure

slide notes

• $150,000 is the average delay damages calculated.
• The disincentive includes $25,000 for the public awareness campaign to alert the public about the closure.
• Incentive is applied for every closure less than 27 used. Disincentive for every closure over 32.
• Did not use the software for LCCA.

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slide 11

Alternatives Analysis

Scenario	Closure Duration	Traffic RUC** ($M)	Traffic Delay**(min)	Agency Cost ($millions)	TotalCost** ($millions)	Cost Ratio
1. Original	35 weekends	3	16	78	79	100%
3. Contraflow 55-hr Weekend	35 weekends	119	363	83	123	156%
4. Progressive Continuous	8 weeks	123	363	77	118	149%
5. Traditional Nighttime	1,220 nights	133	22	88	133	168%
6. CSOL 55-hour weekend	20 weekends	69	363	60	83	105%
** Total Cost = 1/3 RUC + Agency Cost

slide notes

• Go over columns. Delay is per closure.
• 2nd alternative dropped out because of safety concerns.
• Alternative 1 required bridge widening
• Alternatives 3,4 would have serious traffic delay impacts, and would be difficult to determine peak dir., but might be tolerable if the duration was short.
• Alternative 5 would take a long time, and still result in a inferior product.
• Alternative 6 was close in value to the original, but would have higher delays, and was not preferred by maintenance.

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slide 12

Road User Costs/Delay

Scenario	Demand Reduction	1,500 vphpl* capacity Queue (Miles)	1,500 vphpl* capacity Delay (Minutes)	1,500 vphpl* capacity RUC** $(Millions)	1,700 vphpl* capacity Queue (Mile )	1,700 vphpl* capacity Delay (Minute )	1,700 vphpl* capacity RUC** $(Millions)
1 – Original	20%	8	61	20	2	18	2
1 – Original	30%	2	16	3	0	0	0
3 – 55-hour Weekend	30%	51	363	119	34	210	63
3 – 55-hour Weekend	40%	25	179	45	13	81	17
4 – Progressive Continuous	30%	51	363	123	34	210	51
4 – Progressive Continuous	40%	25	179	47	13	81	13
5 – 8-hour Nighttime	5%	8	57	418	-	-	-
5 – 8-hour Nighttime	10%	3	22	133	-	-	-
06/01 – CSOL (Weekend)	30%	51	363	69	34	210	36
06/01 – CSOL (Weekend)	40%	25	179	25	13	81	10
06/02 – 2CSOL (Nighttime)	5%	8	57	120	-	-	-
06/02 – 2CSOL (Nighttime)	10%	3	22	38	-	-	-
* vphpl: vehicle per hour per lane ** RUC: Road User Cost

slide notes

• Note that this was done in a spreadsheet that formed the basis of the module in CA4PRS. It was not a part of CA4PRS when we did our analysis.
• On at least one weekend, our vphpl approached 2000.
• Actual delay was generally between 10-15 minutes during peak hours.

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slide 13

Road User Costs/Delay

slide notes

None.

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slide 14

Stage Analysis (Sample)

Stage	Station Start	Station End	No. of Lanes	Length (m)	Length (lane-km)	Rehab Type	Total (lane-km)	55-hour Closures Estimate
4B, 4C	836+81	837+81	1	100	0.1	CLR	2.5	2
4B, 4C	SB I-15 Conn WB SR-60	SB I-15 Conn WB SR-60	2	773.2	1.546	CLR	2.5	2
4B, 4C	SB I-15 Conn EB SR-60	SB I-15 Conn EB SR-60	2	1430.5	0.858	RSR	2.5	2
2A	7+40	11+79	2	439	0.878	CLR	1.28	1
2A	Jurupa On-ramp SB I-15	Jurupa On-ramp SB I-15	2	500	0.4	ACR	1.28	1
2B	20+90	22+77	2	187	0.374	CLR	3.01	3
2B	22+77	28+51	1	574	0.574	CLR	3.01	3
2B	28+51	33+03	2	452	0.904	CLR	3.01	3
2B	20+96	28+95	1	799	0.24	RSR	3.01	3
2B	WB I-10 CONN SB I-15	WB I-10 CONN SB I-15	1	337.7	0.338	CLR	3.01	3
2B	SB I-15 Jurupa Off-ramp	SB I-15 Jurupa Off-ramp	2	500	0.4	ACR	3.01	3
2B	WB I-10 Conn SB I-15	WB I-10 Conn SB I-15	2	300	0.18	RSR	3.01	3
Note: CLR=Continuous Lane Reconstruction; RSR=Random Slab Replacement; ACR=Asphalt Concrete Rehabilitation

slide notes

This is a more detailed analysis of the original alternative. Used to determine:

• Incentive/Disincentive
• Number of weekends needed (min/max)
• Working Days
• Controlling operations
• Good check to make sure our staging works, and that the Contractor has sufficient access.

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slide 15

Traffic Study (Dynameq)

Closure	Study 1 Delay (min)	Study 2 Delay (min)
WB10-SB15	5.5	8.4
EB10-SB15	4.1	7.7
SB15-WB10	4.5	72.6
NB15-E/W10	5.8	58.6
EB10-NB15	5.8	8
Reduce SB 15	3
SB15-E/W60		121.4

slide notes

• Contracted 2 traffic studies for this project. The second evaluated the first.
• Studies looked at 6 closures
• Variables hard to predict: Diversion, detour usage (especially in urban area), effects of economy, user learning
• Reduce SB 15 will not be done.
• WB10-SB15 – Actual, closed EB-SB as well. Detour? Delay < 10 min
• EB10-SB15 – See previous.
• SB15-WB10 – Closed SB-EB at the same time, and 4th St onramp. Delay < 10 min. Detour at Jurupa?
• NB15-E/W10 – Have not done yet.
• SB15-E/W60 – Delay < 10 minutes for at least 2 out of 3 of the closures. 1 closure with delays a bit longer, but still under 30 minutes.

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slide 16

Schedule

• NTP with CA4PRS study: May 2005
• 30% PS&E: February 2006
• Draft CA4PRS Report: March 2006
• CA4PRS study: October 2006
• 60% PS&E: January 2007
• Advertise: September 2008
• Award: January 2009
• Construction Begins: April 2009
• Anticipated Completion: December 2010

slide notes

None.

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slide 17

VALIDATION OF RESULTS

slide notes

• We have finished all of the weekend closures.
• About 18 closures used, so the Contractor got the full incentive.
• As is often the case, the Contractor changed many things in the construction staging, and was very aggressive in pursuing the incentive.
• We also experienced lower traffic delays than anticipated, we believe in part due to the economy, and in part due to our public awareness efforts.

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slide 18

Screenshots

slide notes

• Objective/Scope is changed for each closure.

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slide 19

Screenshots

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None.

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slide 20

Screenshots

slide notes

• Couple times they had two pavers out there, but I don't believe they ever operated them simultaneously, due to lack of crews.

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slide 21

Screenshots

slide notes

• Note the user-defined section. Need to define the base more, since it was placed in two lifts.
• Set concurrent double lane/single lane as needed. May need to do portions of a stage separately.
• Sometimes our outside lane width was 2 feet wider.

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slide 22

Screenshots

slide notes

• Note the constraint resource.

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slide 23

Inputs: Predicted Vs. Actual

Tab	Input	Study	Actual	Unit	Notes	Default Values
Activity Constraints†	Mobilization	3	1	hrs		2-3
Activity Constraints †	Demobilization	2	Varies	hrs		4-6
Activity Constraints†	Concurrent - Demo to Base	15	11	hrs		1-2 (Sequential), 9-11 (Concurrent)
Activity Constraints†	Concurrent - Base to PCC	8	5	hrs		1-2 (Sequential), 9-11 (Concurrent)
Resource Profile	Demo Hauling Truck	22	22	tonne		22
Resource Profile*	Demo Trucks per hour per team	10	10	ea		10 for cut & lift, 12 for impact methods
Resource Profile*†	Demo Packing Efficiency	0.5	0.55	%	Used impact method instead of cut & lift	0.5 for cut & lift, 0.6 for impact
Resource Profile†	Demo Number of Teams	2	3	ea	BIG IMPACT!	2
Resource Profile*	Demo Team Efficiency	0.7	0.7	%
Resource Profile††	Base Delivery Truck Cap.	10	6	m3	Used end dumps instead of bottom dumps	10 for buttom dump, 6 for end dump
Resource Profile†	Base Trucks Per Hour	8	16	ea		10
Resource Profile	Base Truck Packing Eff.	100	100	%
Resource Profile*	Batch Plant Capacity	90	90	m3/hr		100
Resource Profile	Concrete Delivery Truck Cap.	6	6	m3		6-7
Resource Profile	Concrete Trucks Per Hour	15	15	ea		15
Resource Profile	Concrete Truck Packing Eff.	100	100	%
Resource Profile*	Paver Speed	2	2	m/min		2
Resource Profile	Number of Pavers	1	1	ea	Sometimes double-lane width
Schedule Analysis ††	PCC Thickness	290	315	mm	345 mm for mainline lanes (315 for connectors)
Schedule Analysis	Base Thickness	152.4	150	mm
* Unable to verify actual value in field †Difference speeds up actual production ††Difference slows down actual production

slide notes

• Explain the table headings
• Got this input from talking to construction inspectors, and reviewing the inspector diaries.
• Haven't been able to verify every actual input (marked with an asterisk), but we have gotten most of the critical ones.
• Define orange vs. blue highlighting
• Contractor has really understood that the demolition operation is often the critical operation.
• The two slow downs have minimal impact (only minor slow down)
• Show defaults. Note that at the time of analysis, defaults were not included with the program.

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slide 24

Predicted Vs. Actual

• Random slabs as night work
• Sometimes paving two lanes wide on connectors
• Combined stages
• Concurrent vs. Sequential

slide notes

• Demo efficiency was validated by how the contractor performed the Super-Slab work: Fort Miller stated that they have seen very few contractors as efficient as this one on the demo operation.

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slide 25

Predicted Vs. Actual (PRELIMINARY)

Stage Plan1	Stage Study1	Stage Description	No. of Weekends Study2	No. of Weekends Actual2	No. of Weekends Revised Inputs3	Notes
4B,C	5B,C	SB I-15 connectors to E/W SR-60	2	2		Contractor was restricted by width of connector, which forced him to pave one lane at a time. Only 2 demo teams used. Thus very similar to study
2B,C	2B,C	SB Jurupa offramp, W10-S15 conn, E10-S15 conn	4	2	2	Study had separate closures for 2B, 2C. Contractor chose to combine stages.
2D,E	2D,E	SB I-15 connectors to E/W I-10	5	2	2	Contractor may have included more in 2E,F combination, also need to determine how contractor handled 3-lane widths
2E,F	2E,F	Fourth St SB ramps	3	1	1	Added 2E work north of S15-E10 connector diverge
Footnotes (Column descriptions): 1"Plan" is the stage designation as it is called out on the project plans. "Study" is the stage designation as it is called out in the design study. Differences exist because of changes that occurred between when the study was completed and the project design was finished. 2"Study" is the number of closures (weekends) estimated to be needed by the design study to complete the work for the stage. "Actual" is the number of closures actually required to complete the work. 3"Revised Inputs" indicates how many closures were estimated to be needed using the revised inputs for CA4PRS shown in the previous slide.

slide notes

• Read footnotes later.
• This is PRELIMINARY. Used stages that required more than 1 closure.
• Explain: This was create merely by running the revised inputs on the same lane-kilometer objective.
• On the first line, Contractor was restricted by the location to work in a manner very similar to what the study had predicted.
• Second line, the Contractor combined stages, but the study had them separately.
• Third line needs more work to determine why the Contractor was able to perform the work in 2 closures. This highlights the challenge of analyzing this type of work. Contractor significantly revised/combined stages to make work more efficient for his crews.

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slide 26

Time Spent

• Pre-Construction Study:
  • ~160 hours
• Validation of Results:
  • ~40 hours

slide notes

• Time consuming part is data collection and deciding how the contractor will perform the work.
• In validation, these things are know already (and hopefully your CA4PRS file is already set up), so validation occurs much more quickly.
• More to be done on validation.

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slide 27

Lessons Learned

• Construction experience is IMPORTANT
• Design input important for efficiency
• Breadth of knowledge required
  • Traffic
  • Pavement
  • Construction
  • Estimating
• Team approach may be best

slide notes

• A team approach may be best, maybe even a dedicated team.
• D8 is considering a team that would also do things like LCCA, estimate verification, etc.
• Interested to hear suggestions from others with experience with the software.

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slide 28

For Further Study

• More detailed field validation.
• How much did the economy effect traffic volumes, allowing the combined closures?
• What kind of traffic diversion did we get?
• Document experience with precast pavement (Super-Slab) to validate precast module.

slide notes

None.

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slide 29

Contact Info

Jonathan den Hartog
(909) 383-5998
jdenhart@dot.ca.gov

More info:

http://www.dot.ca.gov/hq/research/roadway/ca4prs/index.htm

https://www.fhwa.dot.gov/research/deployment/ca4prs.cfm

slide notes

None.