Building Concrete Overlays on Two Lane Roads Under Traffic U.S. 18 4 1/2 PCC Unbonded Chickasaw / Fayette County, Iowa Partnerships for Progress in Transportation Louisiana Transportation Conference February 17-20, 2013 Session 25 Dr. Michael Ayers, Global Pavement Consultants, Inc.
Acknowledgements Dr. James Cable, Cable Concrete Consultation. The National Concrete Pavement Technology Center, Iowa State University, Ames., Iowa. Federal Highway Administration. Cement and Aggregates Association of Louisiana (CAAL) 2
Project Location
US 18 Bid Information Bid date 10/19/2010 Late start date April 14, 2011 Work period 120 working days Limitations No stringline at centerline Project stages 6 (revised to 5 on site) Number of bidders 6 Bid range - $8.48 million to $10.51 million Prime contractor Manatts Inc. Project length 18.97 miles Project current traffic Chickasaw Co. - 1800 adt/22% trucks Fayette Co. 3050 adt/13% trucks
US 18 Construction Objectives Demonstrate the ability to construct PCC overlays while maintaining traffic on two lane roads. Identify design and construction features that should be included in plans to: Achieve overlay goals. Encourage construction efficiency. Reduce construction costs.
Overlay Conditions First single lane overlay paving, under traffic in Iowa Traffic control by pilot car and flaggers, 24/7
Pre-Paving Project Staging Stage I (Changes in Patching timing) a. Patch (BOP to EOP), maintain traffic with pilot cars b. Construct subdrains, culverts, foreslope flattening, ditch reshaping & erosion control (BOP to EOP) Stage II a. Use TBR/Signals to reconstruct/bridge approaches b. Place shoulder strengthening, TBR/signals/ attenuators & flood lights at four bridges c. Reconstruct bridge approaches, transition pavements ½ at a time with HMA wedge ends
Paving Project Staging Stage III (Changes in Milling length) a. Maintain through traffic w/ lane closure (3.5 miles) & pilot car b. Mill existing HMA surface (18.9 miles) Stage IV a. Pave overlay(eop west to W-14), shoulder & open to traffic Stage V a. Pave overlay (W-14 to BOP), shoulder & open to traffic
Traffic Queue Length Patching & Milling(2mi. zone): 6 to 8 cars / trucks average Paving (3.5 mi. zone): 15 cars / trucks average
Miscellaneous Culvert Work
Subdrain Installation Two mile work zone 48,422 feet of tiling
Full Depth Patches 651 Concrete Patches Average 34 per mile
Full Depth PCC Patches Average 30 per day with sawing in PM Equals about two lane miles/day
Full Depth PCC Patches Average 30 per day with sawing in PM Equals about two lane miles/day
Longitudinal Joint Patching Prep.
Longitudinal Joint Patch Repair
Bridge Approach & Transitions
End of Paving Temp. Transitions
Overlay Survey & Concrete Yield *Milling limits set at 1/2 to 1 1/2 deep at centerline * One mile test section topo to: - Identify section spacings (25 or 50 ft.) - Number of survey shots/section (3, 5 or 9) - Determine basis for value engineering proposal * Test Section Results Yield changed from 26% average overrun to average of 6% after milling to new profile depth Survey interval established at 50 ft. Nine shot survey section for best yield fit Nineteen miles surveyed 3D model established optimum profile model for use by milling and paving machines
Survey existing surface Develop database Create profile Three wire level z coordinates GPS x, y coordinates Survey GPS / Total Stations
Milling of HMA Seven foot wide mill head Cut (½ to 1 ½ ) at centerline Based on profile grade Centerline pass by total stations (25 to 30 ft. per minute) Exterior pass by joint match (1/2 to 1 mile per hour)
Haul Road Selection
Tie Bar Location & Installation
Staging of PCC Overlay
3.5 Mile Timeline for Opening to Traffic 1.0 day- cut trench and lay tied steel (may include last safety edge) 2.5 day- Overlay Paving 1.5 day- Curing 1.0 day- Shouldering 1.0 day- Painting and Signing 7.0 days- Open to traffic via Pilot Car.
Traffic Shift
Stringless Paving for PCC Overlay
Stringless One Lane Paving Control
PCC Overlay Paving
Overlay Finishing Operations
PCC Joint Development
Finish Shouldering
US 18 Overlay Conclusions Single lane overlay construction under traffic was successful Multiple traffic work zones are necessary to optimize construction forces and time Staging preoverlay and overlay operations separately was beneficial. Timely concrete delivery requires owner/contractor cooperation Future improvements in the contract documents can reduce costs and increase construction efficiency.
Michael E. Ayers Global Pavement Consultants, Inc. mayers@globalpavements.com www.globalpavements.com Phone 217-621-3438