2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Moncef Nehdi, Western University
Mr. Sammy Wong, Con Cast Pipe
Mr. Abdul-Aziz Younis
Reinforced Concrete Pipe Design with Single Elliptical Steel Cage Reinforcement
Abdullah S. Ramadan1, Abdul-Aziz Younis1, Lui Sammy Wong1,2 and Moncef L. Nehdi1
1 Department of Civil and Environmental Engineering, Western University, London, ON, Canada, N6A 5B9
2 Con Cast Pipe, 299 Brock Rd S, Guelph, ON N1H 6H9
Reinforced Concrete Pipe (RCP) relies primarily on its own structural strength rather than the bedding material around the pipe. It has been used in North America for over a century, with reliable performance. However, this industry has been experiencing declining market share for several years due to competition from the lightweight flexible pipe industry and tepid technological advancements. RCP strength is classified according to its design crack load using the Three-Edge Bearing Test (TEBT), which is defined as the load capacity without producing a 0.3 mm wide and 300 mm long crack. The test is destructive, applying a concentrated load along the crown of the pipe. The most common form of reinforcing RCP is the traditional double (inner and outer) steel-cage reinforcement. Current Canadian and American standards allow for the use of a single elliptical steel cage reinforcement as an alternative to the double cage. Single elliptical steel cage reinforcement can offer more effective design since the steel is more favourably positioned at the tensile face of the pipe. However, single elliptical steel cage reinforcement is not commonly used in the industry as its performance is not fully understood, coupled with manufacturing limitations of the elliptical steel cage. The goal of this study is to explore the structural performance of RCP reinforced with single elliptical steel cage reinforcement in comparison with traditional reinforcement. RCP specimens were tested under the TEBT, with the load deflection data collected using Linear Variable Displacement Transducers (LVDT) to further analyze the structural behavior. The study confirms that RCP with single elliptical steel cage reinforcement can provide significant cost reduction in both material and labour without compromising structural performance. The study also provides guidance for designing single elliptical steel reinforcement in RCP.
Keywords: Reinforced, Concrete, Pipe, Three-Edge Bearing Test, Design, Elliptical Reinforcement, Structure.