European guidelines for fire performance evaluation of post-installed anchoring systems are limited to mechanical (e.g., expansive, undercut) mechanisms of load transfer and the steel failure mode, whereas the adhesive bond mechanism remains unaccounted for in chemically bonded anchors. Furthermore, current evaluation methods do not account for the influence of practical testing conditions on temperature profiles along the bonded depth. This paper presents 3D finite element thermal simulations of chemically bonded anchors in uncracked concrete exposed to ISO 834 fire conditions with comparisons to experimental specimens. Five parameters representing application and testing conditions are investigated to assess their influence on temperature profiles along the embedment depth of bonded anchors. A numerical model is proposed based on the results of the numerical simulations to determine thermal data necessary for predicting the load-bearing capacities of bonded anchors using the Resistance Integration Method. The model adopts Eurocode material properties for concrete and steel, with 3D analysis yielding conservative capacity prediction compared to physical fire tests. 3D and 2D simulation results are compared, demonstrating that modelling using 2D heat transfer analysis yields inaccurate temperature profiles compared to 3D modelling. After experimental validation of the proposed model, additional parameters are explored in a numerical parametric study: embedded depth, external length of the anchor element, insulation of the anchor element, and insulation of the concrete element. Results show that the embedded depth has a significant influence on temperature profiles along the bond. Moreover, the external length of the anchor influences temperature profiles, but not beyond 20 mm from the concrete surface.

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Fire design of cast-in place and post-installed anchors in concrete under fire is covered by EN 1992-4, Annex D, allowing steel- and concrete-related failure modes of anchors to be calculated. This informative annex of EN 1992-4 is limited to cast-in place or mechanical anchors, whereas post-installed adhesive anchors remain out of its scope. This paper presents a study of the applicability of the more flexible resistance integration method (RIM), proposed originally for the design of the pull-out resistance of post-installed reinforcement (PIR) by Pinoteau, on bonded anchors in uncracked concrete. This method is validated from a comparison of test results obtained from two research projects conducted at CSTB and TU Kaiserslautern on bonded anchors in uncracked concrete under ISO 834-1 fire conditions. The data considered include tests conducted on anchor sizes from M8-M30 using three different adhesives (two epoxy adhesives and one cementitious mortar). Design of the pull-out resistance under fire using RIM requires numerical calculation of temperature profiles considering models of concrete and steel elements; different assumptions about modeling these elements can produce vastly different end results. Finally, recommendations for assessment procedures for bonded anchors under fire conditions are provided as entry data for design.

Anchor bolts in annular stand-off base plates connecting cantilever sign and signal structures to concrete foundations may experience high shear from base plate torsion and direct shear forces. A three-phase experimental study evaluated the steel shear strength of anchor bolts in grouted and ungrouted annular stand-off base plate connections to concrete. Phase 1 included flush-mounted and ungrouted stand-off base plates with ⅝- and 1-in.-diameter bolts loaded in direct shear. Phase 2 employed a novel torsion test approach on 10 circular groups of six ⅝-in.-diameter bolts installed in flush-mounted, ungrouted stand-off, and grouted stand-off base plates, along with three ungrouted groups of three 1-in.-diameter bolts. Phase 3 comprised one ungrouted and three grouted full-scale annular base plate tests of six 1.25-in.-diameter bolts under predominantly torsion loading. Results from this study suggest that AASHTO's provisions allowing bolt bending stresses to be ignored for anchor bolts with an exposed length of less than one bolt diameter overestimate ultimate strength. The beam model suggested by AASHTO accounting for anchor bolt bending fits experimental data well and is recommended for all ungrouted annular stand-off base plates. The American Concrete Institute's 0.8 reduction factor for steel shear strength of anchor bolts in grouted connections was found to be conservative and is also recommended.

A well-known source of damage to houses in hurricanes occurs when water bypasses failed roof coverings that allow water to enter the interior through joints in the wood roof decks. Closed-cell spray-applied polyurethane foam (ccSPF) sprayed to the underside of the roof functions as a secondary water barrier to mitigate this damage, in addition to its primary function as a thermal barrier. Recent studies at the University of Florida revealed that ccSPF also significantly increases the wind uplift resistance of a wood roof deck due to its strong bond to wood substrates. This presentation describes a research project that investigated the effects of incidental water leakage on the strength of the ccSPF-to-wood bond and on moisture retention characteristics in a wood roof. The two-phased study consisted of the construction and long-term testing of full-scale roof attics exposed to outdoor environmental conditions in Gainesville, FL, and bench-type studies using small-scale roof deck samples. Each roof attic was retrofitted using ccSPF, selfadhered membrane underlayment and/or air gaps between the sheathing and ccSPF. Numerous ½ in. diameter holes (leak gaps) cut into the roofing created sources of water leaks, and we continuously monitored moisture content in the wood in real-time through a web-based application. The wind uplift capacity of roof panels (ultimate failure pressure), were determined at the end of each exposure period. Concurrently, small-scale testing was conducted to measure the tensile strength of the wood-to-ccSPF bond for samples exposed to up to 16 weeks of intermittent water sprays. The moisture distribution in 6 in. x 6 in. wood (OSB and plywood) roof deck samples was also determined, representing common construction patterns such as vertical or horizontal sheathing joints, and the configurations of full-scale retrofit systems. While ccSPF remains highly effective as a structural retrofit despite significant wetting, elevated moisture content occurs within the wood substrate. Successful techniques were demonstrated to mitigate moisture retention, such as use of self-adhered waterproofing membrane or including an underside-deck air gap within the ccSPF retrofit layer that resulted in substantial reduction (90% and 80%, respectively) in moisture contents within the sheathing. The study has led to recommendations for the installation and maintenance of ccSPF-retrofitted residential roofs, and the use of similar wood-foam composite systems in wood-framed buildings. BACKGROUND Failure of roof sheathing during extreme wind events is a common failure mode in residential roofs. The majority of hurricane-related losses are sustained by residential homes and 95% of these are from failures within roof-systems (Baskaran and Dutt, 1997). Inadequate fastening of wood sheathing to roof framing members is the most common failure mode. Roof