Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
6 C H A P T E R 2 Summary of Projects VisitedThis chapter provides brief descriptions about the projects visited. Chapters 3 and 4 provide more detail about the materials, construction, pavement design, and performance of the portland cement concrete (PCC)/PCC and asphalt concrete (AC)/PCC sections, respectively. N279, Near Veghel, Netherlands Numerous exposed aggregate concrete composite sections were built on 17 km of the N279 located in southern Nether- lands in 2000, as shown in Figure 2.1. The Netherlands has a long history of building exposed aggregate concrete (EAC) surfaces. These are subjected to an average of 25,000 vehicles per day, 30% of which are commercial trucks. The sections originally were asphalt but were replaced with two-layer EAC over jointed plain concrete pavement (JPCP) to ensure that the pavement would have improved noise levels and require less maintenance over its lifespan, thereby reducing traffic congestion resulting from maintenance. Measurements in the Netherlands have shown that the EAC noise level is about 2 dB(A) less than dense-graded, hot mix asphalt. A6, Near Amberg, Germany The A6 motorway in Germany, at the time of the R21 teamâs visit, was in the process of construction that would connect the two halves of A6, thereby allowing the roadway to run uninterrupted across Germany. The A6 construction project involved 21 km of two traffic lanes in each direction, as shown in Figure 2.2. The project was entirely EAC/PCC with exposed aggregate surfacing (or waschbeton, as it is known in German). Work began on the project in March 2004, and it was completed in September 2008. According to 2005 esti- mates by the German Federal Highway Research Institute (BASt), the A6 motorway receives as many as 70,000 to90,000 vehicles per day (1). Although the eastern stretch of A6 currently receives lower traffic volumes (20,000 to 30,000 vehicles per day), the project contractor designed the pave- ment with the higher traffic volumes of other stretches of A6 in mind. A93, Between Brannenburg and Kiefersfelden, Germany The A93 motorway in Germany, which connects Munich to Innsbruck, is shown in Figure 2.3. Several full-scale test sec- tions in various texturing methods for PCC pavements exist along this roadway. A93 is a main connector to Italy and, as such, receives a great deal of commercial truck traf- fic. A 2005 estimate by BASt states that the A93 motorway in this region receives 50,000 to 70,000 vehicles per day (1). The sections examined along A93 were spaced at intervals between Brannenburg and Kiefersfelden. These sections originally were constructed in 1995 and 1996 as two-layer pavements with a variety of longitudinal burlap drag, tin- ing, and EAC. One section was diamond ground after a few years. Another section received a stone matrix asphalt (SMA) surfacing just after placement of the concrete. Some of the pavement was recycled into new two-layer EAC pavements. A99, Near Ottobrunn, Germany The construction of an off-ramp onto the A99 motorway near Ottobrunn, shown in Figure 2.4, includes the whitetop- ping of existing asphalt pavement. A 2005 estimate by BASt states that the A99 motorway near Ottobrunn receives more than 90,000 vehicles per day (1). Though whitetopping is not relevant to R21, the project was notable for three rea- sons: it is the first whitetopping project in Germany, it features fiber-reinforced panels, and the panel texture is
7 Courtesy of A. van Leest of CROW, Netherlands. Figure 2.1. Location of N279 test sections reviewed by the R21 delegation.Figure 2.2. Location of A6 construction project near Amberg, Germany.EAC. Later sections will detail the rare combination of fiber reinforcement and EAC. A1, Near Eugendorf, Austria The A1 motorway (known as the Westautobahn in Austria) is an important roadway that connects Salzburg and Vienna, as shown in Figure 2.5. A1 is 292 km long and is notable because it was the first motorway to be constructed in Austria, the final sections having been completed in the 1970s. The full length of A1 was originally constructed of PCC pavements of varying designs. Over the years, sections of A1 have been rehabilitated in several ways. One of these rehabilitated sections is a two-layer EAC pavement reconstructed in 1993 near Eugendorf. This section, shown in Figure 2.6, receives average daily traffic of 56,000 vehicles (12% trucks). A1, Near Regau, Austria The two-layer concrete pavement section along A1 near Regau, shown in Figure 2.7, was originally constructed between 1963 and 1966 without an EAC texture. These sections, more than 40 years old, are currently slated for
8 Figure 2.3. The A93 motorway near Brannenburg and Kiefersfelden, Germany.Figure 2.4. The A99 motorway near Ottobrunn, Germany.reconstruction and additional lanes. This section receives average daily traffic of 56,000 vehicles (12% trucks). A1, Near Vorchdorf, Austria The two-layer concrete pavement section shown in Fig- ure 2.8âalong A1, near a toll station at Vorchdorfâwas recon- structed in 1999. The section has an EAC texture and receives average daily traffic of 56,000 vehicles (12% trucks). A1, Near Traun, Austria The two-layer concrete pavement section along A1 near the intersection of A1 and A25 near Traun, shown in Figure 2.9, was reconstructed in 1994. The section has an EAC texture. The section of A1 immediately before the merger with A25 receives average daily traffic of about 55,000 vehicles per day (truck traffic not indicated). The section of A1 immediately after the merger with A25 receives about 100,000 vehicles per day. A12, Near Utrecht, Netherlands This section is located west of Utrecht on the A12, between kilometers 64.36 and 67.66 (this is just before exit 19), as shown in Figure 2.10. The section consists of three lanes in the southbound direction and inner and outer shoulders.
9 © 2008 Google. Map data © 2008 Tele Atlas. Figure 2.5. The 292-km A1 motorway (Westautobahn) in Austria.© 2008 Google. Map data © 2008 Tele Atlas. Figure 2.6. The A1 motorway near Eugendorf, Austria.Figure 2.7. The A1 motorway near Regau, Austria.
10Figure 2.8. The A1 motorway near Vorchdorf, Austria.Figure 2.9. The A1 motorway near Traun, Austria.© 2008 Google. Map data © 2008 Tele Atlas. Figure 2.10. The A12 motorway between Arnhem and Utrecht, Netherlands.
11© 2008 Google. Map data © 2008 Tele Atlas. Figure 2.11. The A73 motorway in the Province of Limburg, near Venlo in southern Netherlands, built in 2007â2008.This project is a typical heavily trafficked freeway with controlled access that carries a large volume of auto and truck traffic between Arnhem and Utrecht. The porous AC/continuously reinforced concrete pavement (CRCP) was constructed in 1998. A73, Province of Limburg, Southern Netherlands The A73 is a 42-km, four-lane, divided freeway with inner and outer shoulders. The project is located on the A73 free- way in south Netherlands in the Province of Limburg to connect the city of Venlo, via Roermond, to the existing A2 highway near the community of Echt-Susteren, as shown in Figure 2.11. This roadway is a heavily trafficked freewaywith controlled access that carries a large volume of auto and truck traffic. The section includes two layers of porous asphalt surface over CRCP and represents the latest thinking for low noise and other excellent surface characteristics. This type of project has been built in the Netherlands during the past 10 years and has provided excellent performance. The project was nearing com- pletion at the time of visit in May 2008 and was open to traffic. Reference 1. Heavy Traffic on Federal Highways and Federal Roads: Results of Road Survey 2005 (Verkehrsstärken auf Bundesautobahnen und Bundesstrassen: Ergebnisse der Strassenverkehrszahlung 2005). Bundes- anstalt für StraÃenwesen (BASt), Bergisch Gladbach, Germany, 2007/2008.
