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The recent publication of European design and qualification standards for post-installed anchors in seismic applications is a milestone in safe anchoring. A longstanding deficiency in European anchor qualification procedures has been addressed and a new seismic performance category has been introduced: the C2 seismic performance category. In the meantime, the discussion has started to also introduce the C2 category into ACI 355 and ACI 318. The primary aim of this paper is to provide the engineering community with the background and information necessary to understand the idea and rationale of the C2 qualification. After providing a brief background on the subject, the authors compare both the U.S. and European qualification requirements and examine the effect of the enhanced C2 requirements on the approved anchor design strength by an example study and database analysis of European approvals. The consistent system of product approval and the compatibility of the C2 category with the existing anchor design provisions in the United States makes the adoption of the C2 category in ACI standards feasible. A meaningful regulation when designing for the C2 requirements is critical. [ABSTRACT FROM AUTHOR]

The shear behavior of fiber-reinforced-polymer-strengthened reinforced concrete (FRP-strengthened RC) members is not fully developed and accurately predicted because of the lack of accurate constitutive laws for the components of the composite members. This paper presents experimental and analytical investigations of tensile stress-strain relationships of concrete and steel in FRP-strengthened RC members. These stress-strain relationships are required in formulations of softened truss models to predict the shear behavior of the FRP-strengthened RC element. Thirteen full-scale FRP-strengthened RC prismatic specimens with different FRP reinforcement ratios, steel reinforcement ratios, and FRP wrapping schemes were tested under uniaxial tension loading. The results show that the tensile behavior of the concrete and steel is altered because of the externally bonded FRP sheets. Modified constitutive laws are proposed and incorporated in the softened membrane model (SMM) to demonstrate through two tests the behavior of FRP-strengthened RC element subjected to pure shear. Moreover, crack spacing and crack width were studied and compared with existing code provisions. [ABSTRACT FROM AUTHOR]