Ultra-High Performance Concrete: A State-Of-The-Art Report for The Bridge Community

CHAPTER 6. ACTUAL AND POTENTIAL APPLICATIONS

This chapter describes specific applications of UHPC in infrastructure projects. Separate sections contain descriptions of the applications in North America (United States and Canada), Europe, and Asia/Australasia. Potential applications described in the literature are also presented.

NORTH AMERICA

Table 14 provides a list of the applications in the United States and Canada.

Table 14. UHPC applications in North America

The first highway bridge constructed in North America was the Mars Hill bridge in Wapello County, IA.⁽²³⁸⁾ The simple single-span bridge, as shown in figure 13, comprises three 110-ft (33.5-m)-long precast, prestressed concrete modified 45-inch (1.14-m)-deep Iowa bulb-tee beams topped with a cast-in-place concrete bridge deck. Each beam contained forty-seven 0.6-inch (15.2-mm)-diameter, low-relaxation prestressing strands and no shear reinforcement.

Figure 13. Photo. Mars Hill Bridge, Wapello County, IA

One span of the 10 spans of the Route 624 bridge over Cat Point Creek in Richmond County, VA, was built using UHPC.⁽⁴⁵⁾ (See figure 14.) Bulb-tees with a depth of 45 inches (1.14 m) and a length of 81 ft 6 inches (24.8 m) were used. The specified compressive strengths were 12.0 ksi (83 MPa) at release of the strands and 23.0 ksi (159 MPa) for design. The beams did not contain any nonprestressed shear reinforcement.

Figure 14. Photo. Route 64 over Cat Point Creek, Richmond County, VA

Following extensive research and testing by FHWA, a UHPC bridge using pi-shaped girders was constructed in Buchanan County, IA, in 2008.^(239,250) (See figure 15.) The shape is named after the Greek letter . The cross section, shown in figure 16, is similar to a double-tee section but with bottom flanges on the outside of each web. Three pi-girders were used in the central 51-ft 4-inch (15.6-m)-long center span of the three-span bridge.

Figure 15. Photo. Jakway Park Bridge, Buchanan County, IA

Figure 16. Illustration. Cross section of pi-shaped girder

In New York State, several bridges have been built using field-cast UHPC to create connections between adjacent precast concrete elements.⁽²⁴¹⁾ (See figure 17.) These applications take advantage of the short development lengths that can be used for splice lengths of nonprestressed reinforcement in UHPC. The same technique was used on the transverse joints over the piers of the Keg Creek Bridge, IA, to establish continuity for live load and in the longitudinal joints between deck panels. The use of UHPC in the construction of connections is described by Graybeal.⁽²⁵¹⁾

Figure 17. Illustration. Cross section showing CIP UHPC connection between precast beams

Little Cedar Creek in Wapello County, IA, used 14 UHPC waffle panels for the deck on a 60-ft (18.3-m)-long 33-ft (10.0-m)-wide concrete bridge. ⁽²⁴²⁾ The panels were 15 ft by 8 ft by 8 inches deep (4.6 m by 2.4 m by 203 mm deep) at the deepest point, with the waffle squares having a thickness of only 2.5 inches (64 mm). All connections between adjacent panels and from panels to the precast, prestressed concrete beams used UHPC.

The first bridge to use UHPC in Canada was the pedestrian/bikeway bridge in Sherbrooke, Quebec, as shown in figure 18.⁽²⁾ The structural concept consists of a space truss with a top UHPC chord that serves as the riding surface, two UHPC bottom chords, and truss diagonals that slope in two directions. Each diagonal consists of UHPC confined in 6-inch (152-mm)-diameter stainless steel tubes. The bridge was constructed from six prefabricated match-cast segments with two half-spans assembled prior to erection across the river to create a 197-ft (60-m)-long span.

Source: Lafarge

Figure 18. Photo. Pedestrian bridge, Sherbrooke, Quebec, Canada

Other bridges in Canada that have used UHPC are listed in table 14. The applications include longitudinal and transverse joints between precast components, shear connector pockets between beams and slabs, and a precast post-tensioned tee section for a pedestrian bridge. See Figure 19. Most of the applications have been in Ontario with leadership by the Ministry of Transportation.

Source: Lafarge

Figure 19. Photo. Glenmore/Legsby pedestrian bridge, Calgary, Alberta, Canada

EUROPE

UHPC has been used in bridges in Austria, Croatia, France, Germany, Italy, the Netherlands, Slovenia, and Switzerland as listed in table 15.

Table 15. UHPC applications in Europe

The Bourg-Les-Valence bridges in France are claimed to be the first UHPC road bridges.⁽²⁵⁶⁾ Each bridge consists of two spans made continuous with a CIP UHPC connection between spans. The cross section consists of five spliced pretensioned beams that resemble a double-tee with the addition of bottom flanges similar to a pi-shaped section. Beam lengths are 67.3 and 73.8 ft (20.5 and 22.5 m). The only nonprestressed reinforcement is provided where the components are joined together longitudinally or transversely and at locations of attachments. UHPC was used in the longitudinal joints between beams.

The PS34 Overpass on the A51 motorway in France is a precast, post-tensioned, single-cell box girder bridge with a length of 155.5 ft (47.4 m). ⁽²⁵⁷⁾ The cross section has a constant depth of 63 inches (1.60 m), a top slab thickness of 5.5 inches (140 mm), and web and bottom slab thickness of 4.7 inches (120 mm). The bridge is post tensioned longitudinally with six external tendons.

The St. Pierre La Cour bridge in France consists of 10 UHPC precast, prestressed concrete I-beams spaced at 55-inch (1.395-m) centers with a simple span length of 62.3 ft (19 m).⁽²⁵⁷⁾ The deck consists of 1-inch (25-mm)-thick UHPC precast panels and an 8-inch (200-mm)-thick CIP deck.

According to Fehling, the first UHPC bridges in Germany were built in Niestetal near Kassel with span lengths of 23.0, 29.5, and 39.4 ft (7, 9, and 12 m).⁽²⁶⁰⁾ The longest span used a shallow trough section and was post tensioned. The other two spans used a pi-shaped section and were pretensioned. Two other bridges using the pi-shaped cross-section were built near Friedberg and Weinheim with span lengths of 39.4 and 59.0 ft (12 and 18 m), respectively.

The Gaertnerplatz bridge, a pedestrian/bicycle bridge across the Fulda River in Kassel, Germany, is a six-span structure with a total length of 437 ft (133.2 m) and a main span of 118 ft (36 m).⁽²⁶¹⁾ The structural system is a variable-depth space truss consisting of two top UHPC chords and a single bottom tubular steel chord. The diagonal tubular steel chords are inclined both longitudinally and transversely. The deck spans between and cantilevers beyond the two top chords for a total width of 16.4 ft (5 m). Its thickness varies from 3.1 to 3.9 inches (80 to 100 mm). The deck is glued to the top chords.

In Slovenia, a bridge deck was overlaid with 1 to 1.2 inches (25 to 30 mm) of UHPC.⁽²⁶⁶⁾ An inspection 2 years after installation showed no damage, cracks, or spalling. Applications in Switzerland include rehabilitation and widening of an existing bridge, protection layers to repair a crash barrier and bridge piers, and flooring for a footbridge.^(267,268)

ASIA AND AUSTRALASIA

UHPC applications for highway infrastructure in Australia, Japan, Malaysia, New Zealand, and South Korea are listed in table 16. Descriptions of some of these bridges are provided below.

Table 16. UHPC applications in Asia and Australia

The Shepherds Creek bridge in Australia is a single 49-ft (15-m)-span bridge with a 16-degree skew.^(269,271) The superstructure consists of sixteen 23.6-inch (600-mm)-deep precast, prestressed UHPC beams spaced at 51 inch (1.3 m) centers. These support 1-inch (25-mm)-thick precast UHPC panels and a 6.7-inch (170-mm)-thick CIP reinforced concrete deck.

Numerous bridges, as listed in table 16, have been constructed in Japan beginning with the Sakata-Mirai bridge in 2002.^(269,276) (See figure 20.) This footbridge consists of pretensioned box girder segments that were post tensioned together to form a single span of 161 ft (49.2 m).

Most of the UHPC footbridges in Japan consist of precast segmental U-beams with a separate top slab that is integrally connected to the U-beam. The U-beam segments are connected longitudinally with a CIP joint and post tensioning.

The Horikoshi Highway C-Ramp bridge was Japan's first highway bridge using UHPC.⁽²⁷⁶⁾ The composite girder bridge is composed of four pretensioned UHPC I-shaped girders and a conventional CIP concrete deck. The use of UHPC in the girders allowed reduction of the number of girders from 11 to 4. The weight of each girder was less than it would have been with conventional concrete, allowing the use of a smaller crane. The overall weight of the bridge was reduced by 30 percent.

Source: Lafarge

Figure 20. Photo. Sakata-Mirai bridge, Sakata, Japan

The Toyota Gymnasium footbridge is a two-cell segmental box girder using match-cast segments and dry joints with epoxy. To overcome the shortening caused by autogenous shrinkage of the lead segment before casting the next segment, a steel plate was used at the end of the lead segment and becomes the end form for the new segment.⁽²⁷⁶⁾

The construction of Runway D at Tokyo's Haneda International Airport used 9.8-inch (250-mm)-deep UHPC panels spanning between longitudinal steel girders above the Tamar River.⁽²⁷⁶⁾ The panels consist of ribs supporting a slab with a minimum thickness of 3 inches (75 mm). This reduced the dead load of the slab by about 56 percent compared with conventional concrete. Approximately 6,900 panels were produced for this application.

The Sunyudo (Peace) footbridge in South Korea is an arch bridge with a main span of 394 ft (120 m).⁽²⁷⁵⁾ (See figure 21.) It is built from six precast, post-tensioned pi-shaped sections 4.3 ft (1.30 m) deep. The upper flange is a ribbed slab 1.19 inches (30 mm) thick with transverse prestressing. The webs of the pi-shaped section are 6.35 inches (160 mm) thick and inclined outward at the bottom. The six precast sections are post tensioned together by tendons located in the upper and lower haunches of the section. This bridge is the longest span UHPC bridge in the world.

Source: Rualt Philippe

Figure 21. Photo. Footbridge of Peace, Seoul, South Korea

REALIZED AND POTENTIAL SECURITY APPLICATIONS

Significant research and development efforts have also occurred with regard to the potential security applications afforded by UHPC. Infrastructure security can be a critical consideration, thus leading to opportunities to use UHPC components either as barrier protection systems or as inherent portions of the critical infrastructure. A state-of-the-art report on fiber-reinforced UHPC with a focus on security applications was completed in 2010.⁽²⁸⁰⁾

Research on the mechanical properties of UHPC when subjected to high strain rate loading has been completed by Parent et al., Ngo et al., Millard et al., Habel and Gauvreau, and Millon et al. (See references281, 282, 283, 284, and 285.) Blast resistance testing has been reported by Wu et al., Ngo et al., and Rebentrost and Wight. (See references 286, 282, 287, and 288.) Penetration resistance tests have been reported by Rebentrost and Wight^(287,288) and by Nöldgen et al.⁽²⁸⁹⁾

OTHER POTENTIAL APPLICATIONS

This section identifies other potential applications found during the literature search.

Almansour and Lounis compared the design of a prestressed concrete girder bridge using either UHPC or HPC in the girders.⁽²⁹⁰⁾ The design of the UHPC bridge was based on a combination of the Canadian Highway Bridge Design Code (CHBDC) and the AFGC-IR-02. ^(291,4) The design of the HPC bridge was based only on the CHBDC. Both bridges had a span length of 147.6 ft (45 m). Five girders with a depth of 63 inches (1,600 mm) were required for the HPC bridge, and only four girders with a depth of either 35.4 inches (900 mm) or 47.2 inches (1200 mm) were required for the UHPC bridge. The 47.2-inch (1,200-mm)-deep girders represented a conservative design, whereas the shallower sections required more prestressing strands. An optimum solution would be a girder with a depth between 35 and 47 inches (900 and 1,200 mm).

The design of a pilot project for a 39-ft (12-m) span pedestrian bridge using composite steel-concrete construction was reported by Jungwith et al. ⁽¹⁸⁸⁾

Obata et al. examined the use of prefabricated UHPC panels 1.2 inches (30 mm) thick as an overlay for asphalt pavement.⁽²⁹²⁾ The panels were bonded to the asphalt using a grout. About 517 ft² (48 m²) of test pavement was constructed at a test track in Japan using different construction bonding procedures. No cracks were observed before load testing began. Delaminations occurred and increased with the number of wheel passes in some test sections. The authors concluded that early opening of the pavement to traffic is possible with the use of high-strength fast-curing grout.

Oesterlee et al. performed finite element analyses of a conceptual bridge girder using UHPC as an overlay material in place of a conventional waterproofing membrane.⁽²⁹³⁾ The structural response under combined loading from restrained shrinkage and traffic loads showed stresses close to the elastic tensile strength of the UHPC overlay where there was a high degree of restraint. The risk of transverse cracking in the overlay was deemed unlikely.

Schafers and Seim described theoretical and experimental investigations into the composite behavior of UHPC decks on timber beams.⁽²⁹⁴⁾ They conducted shear tests of the glued joint between the UHPC and timber to identify the best adhesives and timber surface preparation methods.

Using finite element modeling and experimental verification, Toutlemende et al. investigated the possible use of UHPC precast ribbed waffle slabs for a bridge deck.⁽¹⁷⁵⁾ The slabs were pretensioned in the transverse direction and then post tensioned longitudinally before being connected to the longitudinal steel girders. The test results were compared with analytical models.⁽²⁹⁵⁾

Vande Voort et al. explored the use of UHPC in H-shaped precast, prestressed concrete piles.⁽²⁹⁶⁾ They used laboratory tests to verify moment-curvature response. Two piles were successfully driven into clay soils and tested under vertical and lateral loads. (See figure 22.) The impact resistance of UHPC for use in piles was investigated by Leonhardt et al.⁽¹²⁷⁾

Source: Iowa State University

Figure 22. Photo. Experimental precast pile made of UHPC

Other potential applications that have been investigated are listed in table 17.

Table 17. Other potential applications of UHPC