Effects of permissible shear stress on the design and construction of reinforced concrete containments

Abstract

Provisions for peripheral, radial, and tangential shear have been conservatively established in the ASME Section III Division 2 Code. The design and construction of reinforced concrete containments to the shear provisions in this Code have resulted in extreme congestion of reinforcement and the associated difficulty in the placement of concrete. This is due to the low permissible shear stresses in the Code. Recent tests have demonstrated that the shear provisions are conservative. However, additional testing is required to quantify all aspects of containment behavior in shear. In this paper, those loads and load combinations that generally govern shear design are reviewed. For these loads, containment behavior is qualitatively discussed. Present Code provisions for allowable shear stresses, including Code Cases, are reviewed with illustrations provided of actual congested regions of containments designed to these provisions. The need for additional testing and for the development of new shear criteria is established.