Click for next page ( 28

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement

Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 27
27 CHAPTER 4 Construction and Evaluation of New Test Sections Selecting Surface Textures style toll plaza. The one-way average daily traffic (ADT) in 2008 for Detailed Evaluation was estimated to be 53,000 veh/day, with 7 percent commer- cial vehicles, and is expected to grow to 84,000 veh/day by 2030. By using a systematic procedure to rank the friction, tex- Construction on this multi-contracted project commenced ture, and noise characteristics of existing texture test sections, in late 2004 with land clearing operations. Major earthwork a few forms of textures were identified as having good poten- began in 2005, and bridge and interchange work and general tial to provide adequate friction and reduced noise character- grading operations started in 2006. Aggregate subbase for the istics. These textures, described in Table 4-1, were selected for mainline roadway was placed in fall 2006 and spring 2007. Hot additional evaluation in newly constructed test sections as mix asphalt (HMA) base and PCC surface paving operations part of a paving project. The evaluation (1) examined the con- were begun in April 2007 and completed in July 2007. Special structability, performance, and durability of the different provisions detailing the construction requirements for the textures; (2) further analyzed their performance and durabil- proposed test sections were developed and incorporated in the ity; and (3) helped identify rational requirements for texture, construction contract documents. friction, and noise. The design cross section of the mainline pavement struc- ture, as shown in Figure 4-1, consists of a 12-in. (305-mm) Identification of a Candidate thick PCC surface resting on a 3-in. (76-mm) HMA base and Paving Project 12-in. (305-mm) dense aggregate subbase. The outside lane, which was chosen as the location for the test sections, is 13 ft Several state highway agencies were asked about their ability (4 m) wide (the center and inside lanes are each 12 ft [3.7 m] to incorporate the selected texturing types in a paving project wide). PCC transverse joints are spaced 15 ft (4.6 m) and and support the field work. Although a few states expressed include 1.5-in. (38-mm) diameter dowel bars spaced 12 in. interest and identified possible projects, they were not selected (305 mm) apart. Longitudinal joints are tied with #6 (0.75-in. because of construction schedule and other constraints. Sub- [19-mm] diameter) tie bars spaced at 12 in. (305 mm). sequently, an offer by the Illinois State Toll Highway Author- ity (ISTHA, now the Illinois Tollway) to construct the test Construction of New Test Sections sections as part of a new alignment construction project in the southwest suburbs of Chicago was accepted. Details of the sub- Mainline PCC paving consisted of two separate slipform ject project and the construction of the various test sections are paving runs. In the first run, the 12-ft (3.7-m) wide center provided in the following sections. and 13-ft (4.0-m) wide outside lanes were paved monolith- ically in each direction. In the second run, the 12-ft (3.7-m) inside lane was paved in each direction, with tie-in to the Project Overview center lane slab. The PCC paving project selected for constructing and test- Placement of the 3-in. (76-mm) HMA base on the dense ing the selected surface textures was the South Extension of the aggregate subbase typically preceded the paving work of the first I-355 North-South Tollway between I-55 and I-80 near Joliet, paving run by 2 to 3 days. Also, a paving gap of about 125 ft Illinois. This project is six lanes wide and 12.5 mi (20.1 km) (38 m) for both directions was required at the toll plaza due long and contains intermittent interchanges and an open road- to the structural work that took place on both sides of the

OCR for page 27
28 Table 4-1. Features of the selected texturing types. Pre-Texture/ Primary Texture Texture No. Secondary Spacing, in. Depth, in. Texture Texture Direction Other (mm) (mm) 1 Heavy Turf Drag (MTD 0.04 in. [1mm], Minnesota Astroturf) 0.75 0.125 2 None Tining Longitudinal - (19) (3.2) Diamond 0.11 3 None Longitudinal - Without jacks Grinding (2.8) Longitudinal 0.75 0.125 Sinusoidal 4 Turf Drag Tining Meander (19) (3.2) Wavea 0.75 0.125 5 Turf Drag Tining Longitudinal - (19) (3.2) 0.75 <0.1 6 Turf Drag Tining Longitudinal Shallow Tining (19) (<2.5) 0.75 0.25 7 Burlap Drag Grooving Longitudinal - (19) (6.4) 0.75 0.25 8 Turf Drag Grooving Longitudinal - (19) (6.4) Georgia 0.5-in. 0.5 0.125 9 Burlap Drag Tining Transverse (12.7-mm) (12.7) (3.2) spacing 0.125 10b Burlap Drag Tining Transversec Variable - (3.2) 11c Participating Agency Standard a Sinusoidal wave with wavelength of 16 2 in. (406 50 mm) and amplitude of 8 2 in. (203 50 mm). b Control sections for reference. c Skewed or nonskewed, depending on joint orientation. roadway. The paving and texturing equipment used in the For the first paving run, the concrete was hauled in on first paving run (center and outside lanes) were as follows: semi-trailer dump trucks and concrete transport trucks and dumped on the 3-in. (76-mm) HMA base in front of the Concrete Paver--25-ft (7.6-m) wide monolithic slipform paver. The PCC was spread, consolidated, and screeded by paver, equipped with spreader, dowel bar inserter (DBI), the paver, and automatically fitted with dowel bars (every 15 ft and tie-bar inserter (TBI); [4.6 m]) and tie bars (inside edge of center slab and at interface Pavement Surface Texturing Machine--25-ft (7.6-m) wide of center and outside slabs). The surface was then manually with front-mount turf/burlap drag, center-mount trans- floated and edged prior to the prescribed texturing (pretexture verse or longitudinal tining carriage, and rear-mount cur- and/or tine) and curing application, which was completed ing compound applicator. using the texturing machine. C L Southbound Northbound 11 ft 13 ft 12 ft 12 ft 14 ft 0.19 in./ft 6-in. HMA Shoulder 12-in. PCC (doweled and tied) 12-in. Dense Aggregate Subbase 3-in. HMA Base Figure 4-1. Pavement cross-section.

OCR for page 27
29 Table 4-2 lists the surface textures that were constructed machine to check accuracy of groove dimensions (i.e., spacing and notes the deviations from the originally planned textures. and depth). Sand patch tests were conducted on heavy turf As noted, the following modifications were made: drag sections within 2 days after placement to check the mean texture depth (MTD) requirement. Table 4-3 provides addi- Addition of a second heavy turf drag section (Texture 1b). tional information on each day's paving, including the weather Elimination of the longitudinal meander tine (Texture 4) conditions and description of the texturing activities. Fig- because of its very high construction cost. ures 4-3 through 4-11 illustrate the paving operations and Addition of a longitudinal tine with heavy turf drag pre- resulting surface textures. texture (Texture 5b). Inclusion of a second texture (skewed variable tine) (Tex- Diamond Grinding and Grooving ture 12). As indicated in Table 4-3, all of the formed or fresh concrete In general, each day of paving associated with the first paving textures (e.g., deep turf drag, longitudinal tining, and trans- run (center and outside lanes) involved a different surface tex- verse tining) at the test site were completed between April 30 ture. Figure 4-2 shows the sequence of paving for the first and May 25, 2007. The three cut or hardened concrete textures paving run, the beginning and ending locations (in stations) were constructed several weeks later (September 29 through of each day's paving, and the texturing applied as part of October 6, 2007), following the completion of paved shoulders the study. Only the specified pre-texture for Textures #3, #7, on which the grinding/grooving equipment could operate. and #8 was applied at the time of paving; the associated Weather conditions during the grooving and grinding opera- grinding/grooving was performed several weeks later. tions were fairly seasonal, with daily highs in the upper 70s to Paving and fresh concrete texturing activities were closely lower 80s and only a trace of precipitation on one day. Grind- monitored and documented. Tire tread depth gauge measure- ing and grooving was performed full-width over the center ments of the various tinings were taken behind the tining and outside lanes. The diamond grinding equipment and Table 4-2. Constructed textures. TEXTURE TEXTURE NO. Primary (spacing depth) Secondary COMMENTS 1a None Heavy Turf Drag (MTD 0.015 0.03 in. (0.4 0.75 mm) 1b None Heavy Turf Drag (MTD 0.025 Section 1b added due to inadequate 0.04 in. (0.6 - 1.1 mm) levels of MTD in Section 1a 2 Long Tine--0.75 in. 0.13 in. (19 mm None 3.2 mm) 3 Long Diamond Grind--0.11 in. (2.8 None mm) (without jacks) 4 Long Meander Tine--0.75 in. 0.13 in. Std Turf Drag Not installed due to high cost. (19 mm 3.2 mm) 5a Long Tine--0.75 in. 0.13 in. (19 mm Std Turf Drag 3.2 mm) 5b Long Tine--0.75 in. 0.13 in. (19 mm Heavy Turf Drag Section 5b added to examine effects of 3.2 mm) heavy turf drag pretexture 6 Shallow Long Tine--0.75 in. <0.1 in. Std Turf Drag (19 mm <2.5 mm) 7 Long Groove--0.75 in. 0.25 in. (19 Burlap Drag mm 6.4 mm) 8 Long Groove--0.75 in. 0.25 in. (19 Std Turf Drag mm 6.4 mm) 9 GA 0.5-in. Tran Tine--0.5 in. 0.13 in. Burlap Drag (12 mm 3.2 mm) 10 Variable Tran Tine--variable* 0.13 Burlap Drag in. (3.2 mm) 11 Tran Tine--1 in. 0.13 in. (25.4 mm Burlap Drag 3.2 mm) (ISHTA "Old" Std) 12 Skewed Variable Tine--variable** Std Turf Drag Section 12 added to evaluate Illinois 0.13 in. (3.2 mm) (ISHTA "New" Std) Tollway's new texturing standard * Spacing varies from 0.38 to 0.81 in. (10 to 21 mm), with average spacing of 0.5 in. (12.7 mm). ** Spacing varies from 0.67 to 2.13 in. (17 to 54 mm), with average spacing of 1.46 in. (37.1 mm).