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High Performance Concrete Pavements
Project Summary

CHAPTER 37. WISCONSIN 2 (Highway 29, Owen) and WISCONSIN 3 (Highway 29, Hatley)

Introduction

In the summer of 1997, WisDOT constructed two experimental concrete pavement projects on Highway 29 to investigate the constructibility and cost effectiveness of alternative concrete pavement designs (Crovetti 1999; Crovetti and Bischoff 2001). Constructed with partial funding from the TE-30 program, one project (designated WI 2) is located in the eastbound lanes of Highway 29 between Owen and Abbotsford, while the other project (designated WI 3) is located in both lanes of Highway 29 between Hatley and Wittenberg (see Figure 99). The WI 3 test sections are also part of FHWA's ongoing Strategic Highway Research Program (SHRP) study. Because of the similarities and complementary design of these two projects, they are considered together in this chapter.

Figure 99. Location of WI 2 and WI 3 projects.

Location of WI 2 and WI 3 projects. An outline map of Wisconsin shows WI 2 on Highway 29 eastbound between Owen and Abbotsford and WI 3 on Highway 29 between Hatley and Wittenberg. WI 2 is west and WI 3 is east of I-39. Madison is shown on I-39 and Milwaukee on I-94.

Study Objectives

The overall objective of these projects is to evaluate the constructibility and cost-effectiveness of alternative concrete pavement designs (Crovetti 1999). Among the different concrete pavement designs and design features being investigated in these projects are (Crovetti 1999):

  • Reduced number of dowel bar across transverse joints.
  • Alternative dowel bar materials for transverse joint load transfer.
  • Variable thickness pavement cross section.

Project Design and Layout

Wisconsin 2

The WI 2 project is located only in the eastbound lanes of Highway 29. It was constructed in September 1997 and includes both alternative dowel bar materials and alternative dowel bar layouts (Crovetti 1999; Crovetti and Bischoff 2001):

  • Alternative Dowel Bar Materials
    • Standard epoxy-coated steel dowel bars.
    • Solid stainless steel dowel bars, manufactured by Avesta Sheffield.
    • Fiber-reinforced polymer (FRP) composite dowel bars, manufactured by Glasforms.
    • FRP composite dowel bars, manufactured by Creative Pultrusions.
    • FRP composite dowel bars, manufactured by RJD Industries.
    • Stainless steel tubes filled with mortar, manufactured by Damascus Bishop.
  • Alternative Dowel Bar Layouts
    • Standard dowel layout (dowels spaced at 305-mm [12-in.] intervals).
    • Alternative dowel layout 1 (three dowels in each wheelpath).
    • Alternative dowel layout 2 (four dowels in outer wheelpath, three in all other wheelpaths).
    • Alternative dowel layout 3 (four dowels in outer wheelpath, three in all other wheelpaths, one dowel at outer edge).
    • Alternative dowel layout 4 (three dowels in all wheelpaths, one dowel near outer edge).

The alternative dowel bar layouts used on this project are illustrated in Figure 100. These layouts were selected to reduce dowel bar requirements while still maintaining standard placement locations used in Wisconsin (Crovetti 1999).

Figure 100. Alternative dowel bar layouts used on WI 2.

Alternative dowel bar layouts used on WI 2. The five dowel bar layouts used on the WI 2 project are illustrated, each spanning the 12-ft inner lane and 14-ft outer lane. All the joints are diagonal. The standard dowel layout uses 26 dowels at 12-in. spacing. Alternative 1 uses three dowels per wheelpath; alternative 2 uses four dowels in the outer wheelpath and 3 dowels in the three inner wheelpaths; alternative 3 uses four dowels in the outer wheelpath plus one extra dowel at the outer pavement edge (same position as dowel 26 in the standard layout) and three dowels in the three inner wheelpaths; and alternative 4 uses three dowels for all four wheelpaths with one additional dowel near the outer pavement edge (same position as dowel 25 in the standard layout).

The nominal pavement design for these pavement sections is a 275-mm (11-in.) JPCP with skewed variable joint spacing of 5.2-6.1-5.5-5.8 m (17-20-18-19 ft) (Crovetti 1999).

The dowel bars were 38 mm (1.5 in.) in diameter and were placed using an automated dowel bar inserter (DBI). The transverse joints were left unsealed.

The pavement was constructed over existing base materials that were salvaged from the in-place structure, including 230 mm (9 in.) of existing dense-graded, crushed aggregate subbase and 125 mm (5 in.) of existing dense-graded, crushed aggregate base. An additional 50 mm (2 in.) of new dense-graded aggregate base was placed prior to the PCC paving.

Figure 101 shows the approximate layout of the 11 test and 2 control sections in the WI 2 project, using the original section nomenclature adopted by the researchers. Nominal 161-m (528-ft) long pavement segments generally consisting of 29 joints were selected from within each test section for long-term monitoring (Crovetti 1999). Table 54 provides the experimental design matrix for the project.

Figure 101. Approximate layout of WI 2 test sections.

Approximate layout of WI 2 test sections. A diagram illustrates the approximate layout of the Wisconsin 2 project. The inner and outer lanes are 12 ft and 14 ft wide, respectively, and both lanes are divided into 14 sections. Each section utilizes 11-in. JPCP Section C1 is 18,785 ft long, and has steel dowels, and a standard dowel layout. Section CP is 1,612 ft long, and consists of FRP composite bars (creative pultrusions), and uses a standard dowel layout. Section GF is 1,555 ft long, is comprised of FRP composite bars (glasforms), and utilizes a standard dowel layout. Section RJD is 1,651 ft long, is made up of FRP composite bars (RJD Industries) and utilizes a standard dowel layout. Section HF is 367 ft long, and utilizes stainless steel tubes filled with mortar (Damascus-Bishop) and the standard dowel layout. The transition section is 59 ft long, and uses steel dowels and the standard dowel layout. Section 3Ea utilizes steel dowels and dowel layout three, and is 1,269 ft long. Section 3S utilizes stainless steel dowels and the dowel layout 3, and is 1,620 ft long. Section 4S is 1,561 ft long, and utilizes stainless steel dowels in a dowel layout four configuration. Section 4E is 6,242 ft long, and is comprised of steel dowels in dowel layout four configuration. Section 3Eb is 5,340 ft long, and uses steel dowels in a dowel layout 3 configuration. Section 2E is 4,218 ft long, and utilizes steel dowels in a dowel layout 2 configuration. Section 1E is 5,268 ft long and uses steel dowels in a dowel layout 1 configuration. Section C2 uses steel dowels in a standard dowel layout, and is 6,504 ft long.
FRP = fiber-reinforced polymer; JPCP = jointed plain concrete pavement

Table 54. Experimental Design Matrix for WI 2
 11-IN. JPCP 17-20-18-19 FT JOINT SPACING
Standard Dowel LayoutAlternative Dowel Layout 1Alternative Dowel Layout 2Alternative Dowel Layout 3Alternative Dowel Layout 4
Standard Epoxy-Coated Steel DowelsSection C1
Section C2		Section 1ESection 2ESection 3Ea
Section 3Eb		Section 4E
Solid Stainless Steel Dowels (Avesta Sheffield)   Section 3SSection 4S
FRP Composite Dowel Bars (Creative Pultrusions)Section CP    
FRP Composite Dowel Bars (Glasforms)Section GF    
FRP Composite Dowel Bars (RJD Industries)Section RJD    
Stainless Steel Tubes Filled With Mortar (Damascus-Bishop)Section HF    
Wisconsin 3

The westbound lanes of the WI 3 project were constructed in June 1997, whereas the eastbound lanes were constructed in October 1997 (Crovetti 1999). The project includes the evaluation of a variable thickness cross section, an alternative dowel bar layout, and alternative dowel bar materials. The variable thickness cross section uses a 275 mm (11 in.) thickness at the outside edge of the outer lane that then tapers to a thickness of 200 mm (8 in.) at the far edge of the inner lane (see Figure 102). The goal is the more efficient use of materials in areas subjected to greater traffic loading, resulting in more cost-effective designs.

Figure 102. Variable cross section used on WI 3.

Variable cross section used on WI 3. The 12-ft inner lane and 12-ft outer lane are both noted over a base, with the outer lane a 14-ft widened slab in the outer lane. The slab is 11 in. thick at the outer edge and tapers to 8 in. thick at the inner edge of the inner lane. A deformed tie bar connects the slabs at the longitudinal joint. A paint stripe defining the outer lane is 2 ft from the edge of the slab.

The following alternative dowel bar materials are also included on the WI 3 project (Crovetti 1999):

  • Standard epoxy-coated dowel bars.
  • FRP composite dowel bars, manufactured by MMFG.
  • FRP composite dowel bars, manufactured by Glasforms.
  • FRP composite dowel bars, manufactured by Creative Pultrusions.
  • FRP composite dowel bars, manufactured by RJD Industries.
  • Solid stainless steel dowel bars, manufactured by Slater Steels.

The nominal pavement design for these pavement sections is a 275-mm (11-in.) JPCP with a uniform joint spacing of 5.5 m (18 ft). However, as previously described, one section has a variable thickness cross section, varying from 275 mm (11 in.) for the outer lane, and then tapering to 203 mm (8 in.) at the edge of the inner lane. The pavement rests on a 150-mm (6-in.) crushed aggregate base course, and the transverse joints contain 38-mm (1.5-in.) diameter dowels and are not sealed.

Six sections are included in the WI 3 project. The approximate layout of the WI 3 sections being monitored is shown in Figure 103. All dowel bars were placed on baskets prior to paving (Crovetti 1999). It is noted that within the section incorporating various FRP composite dowel bars (Section FR), some of the composite dowel bars were improperly distributed between the 3.7-m (12-ft) and 4.3-m (14-ft) baskets, resulting in different manufacturers' bars being placed across some of the inner and outer traffic lanes (Crovetti 1999). The location of the different manufacturers' dowel bars is shown by lane in the blowup illustration in Figure 103.

Figure 103. Approximate layout of WI 3 monitoring sections.

Approximate layout of WI 3 monitoring sections. The eastbound and westbound traffic lanes (two lanes in each direction) are shown, and each direction is divided into a 12-ft inner lane and a 14-ft outer lane. For the three sections in the westbound lanes, Section TR uses 8- to 11-in. jointed plain concrete pavement (JPCP), steel dowels, and a standard dowel layout; Section C1 uses 11-in. JPCP, steel dowels, and a standard dowel layout; and Section 1E uses 11-in. JPCP, steel dowels, and dowel layout 1. For the eastbound lanes, Section RJD uses 11-in. JPCP, fiber-reinforced polymer (FRP) composite dowels (RJD Industries), and a standard dowel layout; Section FR uses 11-in. JPCP, FRP composite dowels (Glasforms, Creative Pultrusions, and MMFG), and a standard dowel layout. Section SS uses 11-in. JPCP, solid stainless steel dowels, and a standard dowel layout.
FRP = fiber-reinforced polymer; JPCP = jointed plain concrete pavement

The experimental design matrix for the WI 3 project is shown in Table 55. Most of the dowel materials are placed in the standard dowel layout, although one section is placed in alternative dowel layout 1. As previously mentioned, all of these sections are included in the SHRP study, and the SHRP code is provided in Table 55 for each section.

Table 55. Experimental Design Matrix for WI 3
 11-IN. JPCP 18-FT JOINT SPACING8- TO 11-IN. JPCP 18-FT JOINT SPACING
Standard Dowel LayoutAlternative Dowel Layout 1Standard Dowel Layout
Standard Epoxy-Coated Steel DowelsSection C1 (SHRP 550259)Section 1E (SHRP 550260)Section TR (SHRP 550263)
Solid Stainless Steel Dowels (Slater Steels)Section SS (SHRP 550265)  
FRP Composite Bars (MMFG, Glasforms, Creative Pultrusions)Section FR (SHRP 550264A)  
FRP Composite Dowel Bars (RJD Industries)Section RJD (SHRP 550264B)  
FRP = fiber-reinforced polymer; JPCP = jointed plain concrete pavement

State Monitoring Activities

WisDOT, in conjunction with Marquette University, is monitoring the performance of these pavement test sections. Four types of monitoring activities are used (Crovetti 1999; Crovetti and Bischoff 2001):

  • Dowel bar location study - 2 months after construction.
  • FWD testing - immediately prior to paving, immediately after paving, and after 6 and 12 months of trafficking.
  • Distress surveys - immediately after paving and after 6 and 12 months of trafficking. The distress surveys are being conducted over a nominal 161-m (528-ft) pavement segment selected from within each test section.
  • Ride quality surveys - using a pavement profiler and measured on the sections after approximately 1 and 3 years of service.

Continued monitoring of these sections, in the form of FWD testing, distress surveys, and ride quality surveys, will continue through 2004 (Crovetti and Bischoff 2001).

Preliminary Results/Findings

Even though these sections are only 3 years old, some significant findings have been revealed through their early monitoring. These findings are described in the following sections by type of monitoring activity.

Construction Monitoring

A dowel bar inserter (DBI) was used during the construction of WI 2. The DBI easily accommodated the various types of dowel bar materials used in the study and the various dowel layout patterns with minimal disruption to the paving operations (Crovetti 1999).

Dowel Bar Location Study

With the purpose of determining the depth, longitudinal position, and transverse position of each dowel bar, a dowel bar location study was performed on the WI 2 project 2 months after construction using an impact echo device (Crovetti 1999). A summary of the study results are provided in Table 56 (Crovetti 1999). Generally, it appears that the dowel bars are slightly deeper than the mid-depth of the slab (140 mm [5.5 in.]), and that some vertical skewing of the dowels occurred across the joint. It should be noted that dowel depth data were inconclusive for the stainless steel tubes and the solid stainless steel dowels, and that the device could not provide exact longitudinal and transverse positions of each dowel end (Crovetti 1999).

Table 56. Summary of Dowel Bar Location Study Results From WI 2 (Crovetti 1999)
TEST SECTIONNO. OF JOINTS TESTEDAVERAGE DEPTH, WEST SIDE OF JOINT, IN.AVERAGE DEPTH, EAST SIDE OF JOINT, IN.AVERAGE DEPTH VARIATION, IN.
C1 (epoxy-coated steel dowel)16.045.860.18
CP (FRP composite dowel)26.175.970.21
GF (FRP composite dowel)56.1260.47
RJD (FRP composite dowel)76.046.050.2
FRP = fiber-reinforced polymer
FWD Testing

FWD testing has been conducted several times since the construction of these test sections. Table 57 summarizes the backcalculated k-value and concrete elastic modulus, as well as the total joint deflection (defined as the sum of the deflections from both the loaded and unloaded sides of the joint) obtained from the FWD testing (Crovetti 1999). Generally, the test results are fairly consistent over time, although greater variability was noticed in the June 1998 tests for both directions, presumably because of higher slab temperature gradients (Crovetti 1999). Apparent increases in total joint deflections may be due to FWD testing conducted in the early morning when upward slab curling is likely.

Table 57. Summary of FWD Test Results for WI 2 and WI 3 Projects (Crovetti 1999).
PROPERTYWI 2WI 3
EB LANESEB LANESWB LANES
Oct-97Jun-98Nov-98Oct-97Jun-98Nov-98Jun-98Nov-98
Dynamic k-value, lbf/in2/in.312255254364324324255222
PCC Elastic Modulus, lbf/in23,560,0003,870,0004,820,0003,970,0005,990,0006,060,0005,290,0006,130,000
Total 9000-lb Joint Deflection, mils8.967.778.186.75.568.486.237.11

Transverse joint load transfer efficiencies were also measured on all test sections using the FWD. Figure 104 illustrates the average transverse joint load transfer for the outermost wheelpath of the WI 2 project, while Figure 105 illustrates the average transverse joint load transfer for the outermost wheelpath of the WI 3 project (Crovetti 1999). For WI 2, the late season tests (October 1997 and November 1998) indicate significantly reduced LTE in the composite doweled sections and in dowel layout 1 as compared to the control sections (Crovetti 1999). The LTE measured in the summer do not indicate any significant differences within the test sections, probably because of the increased aggregate interlock brought about by the closing of the joints due to the warmer temperatures (Crovetti 1999). Overall, the low LTE values of the FRP bars (between 60 and 75 percent in many cases) is a cause of concern.

Figure 104. Transverse joint load transfer for outermost wheelpath on WI 2 (Crovetti 1999).

Transverse joint load transfer for outermost wheelpath on WI 2 (Crovetti 1999). Twelve test sections were tested for load transfer efficiency (percentage) on three occasions: October 1997, June 1998, and November 1998. For the respective test dates, Section C1 tested at approximately 90, 88, and 89 percent; Section CP at 73, 91, and 75 percent; Section GF at 71, 90, and 72 percent; Section RJD at 63, 90, and 68 percent; Section HF at 78, 88, and 77 percent; Section 3S at 77, 95, and 88 percent; Section 4S at 73, 92, and 81 percent; Section 4E at 77, 93, and 89 percent; Section 3E at 79, 94, and 84 percent; Section 2E at 80, 93, and 84 percent; Section 1E at 68, 92, and 81 percent; and Section C2 at 87, 95, and 85 percent.

Figure 105. Transverse joint load transfer for outermost wheelpath on WI 3 (Crovetti 1999).

Transverse joint load transfer for outermost wheelpath on WI 3 (Crovetti 1999). Three sections were tested for load transfer efficiency percentage on three occasions: October 1997, June 1998, and November 1998. For the three measurements, respectively, Section RJD tested at 82, 91, and 64 percent; Section FR at 88, 92, and 80 percent; and Section SS at 89, 93, and 87 percent. Three sections were tested in June 1998 and November 1999: Section 1E tested at 93 and 81 percent; respectively, Section C1 at 94 and 96 percent; and Section TR at 94 percent and 96 percent.

For WI 3, Figure 105 shows that the FRP composite dowel sections and dowel layout 1 experience a reduction in LTE in the November 1998 test results; there is also a slight reduction in the LTE of the stainless steel section (Crovetti 1999). Again, however, the lower LTE values for the FRP bars are a concern.

Distress Surveys

Distress surveys were conducted for both WI 2 and WI 3 in June and December 1998. Some joint distress (spalling, chipping, and fraying of the transverse joints) was observed and is primarily attributable to the joint sawing operations that dislodged aggregate particles near the joint faces (Crovetti and Bischoff 2001). However, this joint spalling has not yet progressed to the point to be considered as low severity based on the Wisconsin DOT Pavement Distress guidelines (Crovetti and Bischoff 2001). Other than the minor joint spalling, no transverse faulting, slab cracking, or other surface distress has been observed to date (Crovetti and Bischoff 2001).

Ride Quality Surveys

Figure 106 presents the average international roughness index (IRI) measurements in the outer lane of the WI 2 and WI 3 pavement sections (Crovetti and Bischoff 2001). These measurements were recorded in the summer of 1998 and the winter of 2000. Although there is some variability in the data, most of the test sections are performing comparably to the control sections (Crovetti and Bischoff 2001).

Figure 106. Average IRI values in the outer traffic lanes of WI 2 and WI 3 pavement sections (Crovetti and Bischoff 2001).

Average international roughness index (IRI) values in the outer traffic lanes of the WI 2 and WI 3 project pavement sections. The IRI values were measured in 1998 and 2000, and the IRI values are noted as in./mi. Thirteen sections were tested for Wisconsin 2, and six sections were tested for Wisconsin 3. The highest IRI scores for 1998 were WI 3’s FR and C1, exceeding 100. For 2000, the highest were also in WI 3, SS, exceeding 100, and C1, approaching 100. The highest three sections for Wisconsin 2 are 4E, 2E, and 3Ea. The highest three sections for WI 3 are RJD, C1, and FR.

Points of Contact

Debbie Bischoff
Wisconsin Department of Transportation
3502 Kinsman Boulevard
Madison, WI 53704
(608) 246-7957

James A. Crovetti
Marquette University
Department of Civil and Environmental Engineering
P.O. Box 1881
Milwaukee, WI 53201-1881
(414) 288-7382

References

Crovetti, J. A. 1999. Cost Effective Concrete Pavement Cross-Sections. Report No. WI/SPR 12-99. Wisconsin Department of Transportation, Madison.

Crovetti, J. A., and D. Bischoff. 2001. "Construction and Performance of Alternative Concrete Pavement Designs in Wisconsin." Preprint Paper No. 01-2782. 80th Annual Meeting of the Transportation Research Board, Washington, DC.

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Updated: 04/07/2011
  
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