CITTO, C.1; SCHULLER, M.2; RUTH, W.3; RUTH, M.4; MURRAY, I.5

1) Structural Engineer, Atkinson-Noland & Associates, Inc., ccitto@ana-usa.com

2) President, Atkinson-Noland & Associates, Inc., mschuller@ana-usa.com

3) President, Masonry Solutions International, wtruth@masonrysolutions.com

4) Executive Vice President, Masonry Solutions International, mkruth@masonrysolutions.com

5) Masonry Solutions International, imurray@masonrysolutions.com

A research project was carried out to develop and evaluate tension capacity of a new type of post-installed masonry anchor system. The retrofit anchor system utilizes a unique undercut hole with a reverse taper injected with specially formulated Compatible Injection Fill (CIF) to bond anchors to surrounding masonry. As part of this experimental investigation, anchors installed in straight-drilled core holes (straight anchors) and in reverse taper-drilled core holes (tapered anchors) were tested in tension to evaluate the beneficial effect of the tapered anchorage.

A two-dimensional finite element (FE) model was developed to study the behavior of grouted anchors that were tested in this experimental program. A parametric study was conducted to investigate the influence of different parameters such as tapered hole geometry, embedment length, and bond strength on the anchor pullout capacity. The performance of tapered anchors is discussed here based on experimental and analytical results and recommendations are provided for optimal taper geometry.

Keywords: Anchor, taper, masonry, Compatible Injection Fill (CIF), grouted anchor, finite element analysis, pullout test.