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1Lateral unrestrained steel beams when subjected to high temperatures may collapse in service by 2 lateral torsional buckling. This instability state may be predicted in the resistance, temperature and 3 time domain. In this work the beam strength is determined in the temperature domain from a batch 4 of numerical and experimental tests, with a specified degree of utilisation and a typical accident 5 temperature rise. 6The experimental set-up is a reaction portal frame especially designed for beam elements under 7 elevated temperatures. The specimens were heated by means of electroceramic resistances and a fibre 8 mat specimen cover is used to increase the thermal efficiency. The material and the beam initial state 9 conditions were considered, the experimental procedure being based on constant mechanical action 10 under increasing thermal load. 11The experimental data was compared with numerical solutions, obtained from a geometric

Valorization of industrial low-value side-streams are of great interest, contributing to boosts in the circular economy. In this context, lignin side-streams of the pulp and paper industry were oxypropylated to produce biobased polyols and tested in the synthesis of rigid polyurethane (RPU) foams. E. globulus lignins, namely a lignin isolated from an industrial Kraft black liquor and depolymerized lignins obtained as by-products of an oxidation process, were used. RPU foams, synthesized with 100% lignin-based polyols and using a 1.1 NCO/OH ratio, were characterized concerning apparent density, morphology, thermal conductivity, thermal stability, and heat release rate (HRR). Foams containing the lignin-based polyols presented densities varying from 44.7 to 112.2 kg/m3 and thermal conductivity in the range of 37.2–49.0 mW/mK. For the reference foam (sample produced with 100% wt. Daltofoam TP 32015 polyol), values of 70.9 kg/m3 and 41.1 mW/mK were obtained, respectively. The achieved results point out the viability of using the generated lignin-based polyols at 100% content in RPU foams, mainly when depolymerized lignins are used. Moreover, fire retardancy was favored when the lignin-based polyols were introduced. The proposed strategies can contribute to establishing the integrated pulp and paper biorefinery concept where material synthesis (polyols and RPU foams) can be combined with chemical production (vanillin and syringaldehyde).

The main goal of this study is to assess the behaviour of soil–cement blocks with incorporation of organic wastes. The problem of waste accumulation exists worldwide and has become a concern in today’s society, leading to enormous environmental damage. One of the possibilities for reducing their environmental impact is the reuse of these wastes in new materials. However, incorporating waste changes the mechanical, physical and thermal properties of the new material. In order to evaluate the potential use of waste in blocks composition, laboratory tests were conducted and the results were analysed. This article presents the fire behaviour of ecological soil–cement blocks with waste incorporation. Therefore, an experimental programme was performed using samples of wall panel with soil–cement blocks. The wall specimen under fire conditions was also analysed by a non-linear transient finite element numerical model, in time and temperature domains, and the numerical and experimental temperature fields were compared.

A new engineering practice in modern buildings is to use beams with web openings to allow the passage of services within the depth of the beam instead of underneath the beam. As the web post failure may occur before the section reaches the limiting temperature, usually an increase in the fire protection may be required for members with web openings in comparison to its equivalent solid section. The aim of this work is to present an experimental study of unloaded solid and cellular beams with circular holes in fire conditions with and without intumescent fire protection. These preliminary tests results are the basis for generating an elemental multi-temperature analysis needed to assess cellular beams with intumescent protection and give experimental results for calibration of further numerical simulations. The experimental results show that, considering the same nominal fire protection thickness, one can obtain a higher fire resistance time for solid beams when compared with cellular beams. The tests performed, with different hole diameters and web-post widths, points that to achieve the same fire resistance time, a cellular beam will need a higher fire protection compared to an equivalent solid beam. Also, a special care is needed when the intumescent coating is applied around the hole to avoid the intumescent contraction, applying for example an over coating.