[This article has been retracted] Fire Performance of Laminated Veneer Lumber (LVL) with Glued-in Steel Rod Connections

Abstract

[This article has been retracted] This article describes an investigation into the fire performance of laminated veneer lumber (LVL) made from radiata pine, with glued-in steel rod connections. To determine charring rates, cone calorimeter tests are carried out on samples of LVL with a number of grain orientations, each for a range of constant heat flux exposures. Full-size load-bearing fire resistance tests are carried out on large cross section LVL beams (with no connections) in a 3 × 4m² full-size furnace, following the ISO 834 curve. Charring rates are found to be similar to solid wood or glulam. To determine connection performance, an experimental investigation is carried out on the axial tensile strength of connections that utilized a threaded steel rod bonded into the timber using two epoxy resins and a composite adhesive. Some specimens are tested at a constant elevated temperature while similar specimens are tested in fire conditions under constant load. The three adhesives give different connection strengths at ambient temperatures and show different strength losses at elevated temperatures. Design recommendations are given in this article.