Dynamic behavior of single and double near-edge anchors loaded in shear

Under the sponsorship of the U.S. Nuclear Regulatory Commission, a research project has recently been completed whose objective was to obtain technica l information to determine how the seismic behavior and strength of anchors (cast-in-place [CIP], expansion, and undercut) and their supporting concre te differ from the static behavior To that end, a research program was carr ied out on the dynamic behavior of anchors in concrete. The research progra m comprised four tasks: 1) static and dynamic behavior of single tensile an chors (250 tests); 2) static and dynamic behavior of multiple tensile ancho rs (179 tests); 3) static and dynamic behavior of near-edge anchors (150 te sts); and 4) static and dynamic behavior of multiple-anchor connections (16 tests). The anchors tested were selected based on their reported frequency of use in nuclear power plants in the US. Anchors included cast-in-place h eaded bolts, grouted headed bolts, two wedge-type expansion anchors, one sl eeve-type expansion anchor, and two undercut anchors. Loading conditions in cluded tension, shear, and combined tension and shear. Test variables inclu ded different concrete types and strengths, loading rate, and the presence of cracks. In this paper the dynamic response of single and double near-edg e anchors loaded in shear is described.