Improvement of Durability of Precast Concrete Member by Granulated Blast Furnace Slag Sand
Toshiki Ayano*1,†, Takashi Fujii*1, Kyoji Niitani*2, Katsunori Takahashi*3, and Kazuyoshi Hosotani*4
3-1-1 Tsushima-naka, Kita-ward, Okayama 700-8530, Japan
*2Oriental Shiraishi Corporation, Tokyo, Japan
*3JFE Steel Corporation, Tokyo, Japan
*4Landes Corporation,Ltd., Okayama, Japan
Concrete deck slabs of bridges are often deteriorated by heavy traffic and freezing and thawing actions. Spraying salt during the winter further promotes the deterioration of concrete. Some reports estimate that the length of highway roads requiring the renewal of deteriorated concrete slabs exceeds 230 km. In order to extend the lifespan of damaged bridge girders, the load for these girders must not be increased. This means that prestressed concrete (hereafter, PC) members are desirable to sustain bridge life, because they can be thinner than reinforced concrete (hereafter, RC) members. In addition, to shorten the period of traffic regulation during renewal construction, precast members should be applied. One problem in manufacturing durable precast concrete is steam curing. When the temperature, period, or both of the steam curing process are inadequate, the effect of air-entraining (hereafter, AE) agents is lost because the warmed air trapped by the AE agent expands and escapes from the concrete. Another problem is concrete fatigue. It is well known that the fatigue lives of concrete slabs in wet conditions are much shorter than those in dry conditions. Concrete slabs are waterproofed immediately after construction, but the waterproofing can be fractured soon after opening bridges, and water can reach the concrete surface. The lifespan of concrete slabs in contact with water often depends on the fatigue of the concrete. Granulated blast furnace slag sand (hereafter, BFS) can enhance the resistance to freezing and thawing actions without using AE agents. Therefore, the resistance to freezing and thawing of concrete mixed with BFS is not damaged by steam curing. The fatigue of concrete in water is also improved by the addition of BFS. Furthermore, BFS can reduce the drying shrinkage of concrete. It is advantageous to restrict the loss of prestress in PC. This study shows that precast PC members with high durability can be manufactured when granulated blast furnace slag is used as a fine aggregate in the concrete. BFS reacts with cement hydrates. It is well known that the carbonation of concrete with ground granulated blast furnace slag (hereafter, GGBF) is much greater than that with ordinary binder. However, BFS does not accelerate the carbonation of concrete. When using granulated blast furnace slag as a fine aggregate, no disadvantage in the concrete properties is detected.
-  Y. Ishikawa, S. Aoyama, N. Tokura, and M. Nishio, “Characteristics of Chrolid Penetration Due to Anti-freezing Agent into Slab Concrete of Steel Girder Bridges,” Procs. of the Japan Concrete Institute Annual Convention, Vol.32, No.2, pp. 1393-1398, July 2010.
-  S. Matsui, “Fatigue Strength of RC slabs of Highway Bridges by Wheel Running Machine and Influence of Water on Fatigue,” Procs. of the Japan Concrete Institute, Japan Concrete Institute Annual Convention, pp. 627-632, July 1987.
-  H. Mitamura, T. Satou, K. Honda, and S. Matsui, “Influence of Frost Damage on Fatigue Failure of RC Deck Slabs on Road Bridges,” J. of structural engineering, A, Vol.55A, pp. 1420-1431, 2009.
-  Y. Fukunaga, T. Imamura, Y. Miura, and M. Tsunomoto, “Concrete Slab Replacement in Heavy Traffic Expressway, – Mukaizano Bridge in the Kyushu Expressway –,” National Report of Japan on Prestressed Concrete Structures, pp. 201-204, Janury 2014.
-  S. J. Virgalitte, M. D. Luther, J. H. Rose, and B. Mather, “ACI 233R-95, Ground Granulated Blast-Furnace Slag as a Cementitious Constituent in Concrete,” American Concrete Institute, Farmington Hills, Michigan, 1995.
-  D. Kwak, K. Uji, K. Kokubu, and A. Ueno, “Evaluation of Pore Structure due to Curing Conditions and Influences of Pore Size on Carbonation of Concrete,” Doboku Gakkai Ronbunshu, No.718/V-57, pp. 59-68, 2002.
-  Japan Road Association, “Design Specifications for Reinforced concrete Highway Bridges,” June 1964.
-  S. Matsuo, H. Yokoyama, K. Hino, and T. Horikawa, “Faitgue Properties of Existing RC Slabs under Wheel Running Machine with Pneumatic Tire,” Procs. of 2nd Symposium on Deck of Highway Bridge, October 2000.
-  T. Fujii and T. Ayano, “Freezing and Thawing Resistance of Concrete with Blast Furnace Slag,” Procs. of NTCC2014, pp. 53-56, 2014.
-  T. Fujii, A. Sugita, and T. Ayano, “Resistance to Freezing and Thawing of Concrete with Granulate Blast Furnace Slag Sand,” Procs. of Conmat 15, pp. 1331-1338, 2015.
-  T. Fujii, A. Sugita, and T. Ayano, “Improvement of Durability of Concrete by Granulated Blast Furnace Slag Sand,” Procs. of the 4th international conference in Sustainable Construction Materials and Technologies (SCMT4), August 2016.
-  A. Sugita, K. Niitani , T. Ayano, and T. Fujii, “Experimental Research of Ultra-high Endurance Prestressed Concrete Member,” Procs. of the 24th Symposium on Developments in Prestressed Concrete, pp. 22-23, October 2015.
-  Japanese Industrial Standards Committee, JIS A 1148-2010, “Method of test for resistance of concrete to freezing and thawing,” 2010.
-  T. Ayano and T. Fujii, “Resistance to Freezing and Thawing Attack of Concrete with Blast Furnace Slag Fine Aggregate,” J. of Japan Society of Civil Engineers, Ser. E2 (Materials and Concrete Structures), Vol.70, No.4, pp. 417-427, 2014.
-  A. Furuta, A. Ueno, K. Kokubu, K. Uji, “A Study on Control of Concrete Bleeding using Slag Fine Aggregate,” Procs. of the Japan Concrete Institute, Vol.27, No.1, pp.97-102, 2005.
-  Japan Society of Civil Engineers, “the Standard Specifications for Concrete Structures: Structural Performance Verification,” 2012.
-  K. Rokugo, M. Iwasa, T. Suzuku, and W. Koyanagi, “Testing Methods to Determine Tensile Strain Softening Curve and Fracture Energy,” Balkema, pp. 153-163, 1989.
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