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Large timber buildings, formed from both light and heavy timber construction, are becoming increasingly common in Europe. Many multiple-occupancy timber buildings, such as apartment blocks, are now constructed to greater heights and in densely populated urban locations. The fire-resistance performance of such timber buildings is generally related to the standard fire test. Alternatively, EN 1995-1-2 may be used to demonstrate fire resistance by means of calculation or numerical modelling. The latter is currently limited to standard fire exposure. In addition, modelling approaches are often avoided as many numerical codes do not normally offer the capability to model timber exposed to fire. The most obvious barrier is incorporating the different tensile and compressive strength/stiffness degradation with increasing temperature. Unlike many other structural materials, it is not possible to define a single relationship between timber Modulus of Elasticity (MoE) and temperature. When timber design is advanced to a ‘performance-based’ level further complexities will arise. For example, the definition of structure temperatures for non-standard fires is a difficult task, and assessment of strength/stiffness degradation on the basis of temperature alone is not sufficient due to char formation. As a result, when cooling is considered, material properties based upon stress state, temperature and temperature history are needed.

To address the above limitations, a number of developments, which can be used with general FEA software, such as DIANA, to design timber structures for fire, are presented. The developments are incorporated via user-supplied subroutines written in FORTRAN code. The routines include code for determining MoE and strength based upon stress state, temperature and temperature history. They are implemented as part of a total strain-based constitutive model. The implementation of the routines is demonstrated using a simple continuous beam. The example is also used to demonstrate how compartmentation provisions and aspects of whole building behaviour can be used to better design large-section timber buildings. Comparisons are made with simple empirical approaches presented in EN 1995-1-2. Extensions to ‘performance-based design’ using parametric fires are also discussed.

The Southern African Institute of Steel Construction has developed a novel cellular beam structure (CBS) for multi-storey buildings that is entirely devoid of concrete. Channel sections between the cellular beams support a complex sandwich flooring system, which contains a fire-resistant ceiling board, metal sheeting, an interior fibre-cement board and an access-flooring system. As for all structures, the CBS requires a fire rating. This paper aims to investigate the thermal behaviour of the CBS using numerical modelling and experimental fire testing, as it has a unique setup.

Experimental fire tests on the flooring system were conducted to validate finite element models, which were developed in ABAQUS. These models were then extended to include floor beams and the structural steelwork.

Good correlations were found between the experimental and numerical results, with temperature variations typically in the range of 0-5%, although with localised differences of up to 20%. This allowed larger finite element models, representing the sandwich floor system of the CBS, to be developed and analysed. A 1-hour rating can be obtained by the system in terms of insulation and integrity requirements.

The CBS allows for more economical steel structures, due to the rapid construction of its modular panels. A suitable fire resistance will ensure the safety of the occupants and prevent major structural damage. Steelwork and flooring temperatures are determined which has allowed for global structural analyses to be carried out.

The originality of this study lies in thermal analysis and testing of a new cellular beam flooring system, through determining behaviour in fire, along with beam temperatures.

This paper aims to present the results of a study on the behaviour of a pre-stressed cable steel truss exposed to fire under fire conditions, basing on the results of a large programme of experimental tests.

The research investigated the deformation and stress change on a pre-stressed steel cable, including the deflection and displacements at different joints and fire behaviour of the pre-stressed steel cable. In other words, the structural behaviours at different loaded pre-stress, the vertical loading, steel cable height, truss dimension and the final temperature were compared in case of fire.

The results showed that the strain of longitudinal chord was far larger than those of the transverse chords, the strains of lower chords were significantly larger than those of the upper chords, strain of the chord near the longitudinal centreline were also larger than those of the outside transverse chords. During heating, the displacement and strain gradually changed from linear to nonlinear with loading, and the yielded chord had also in an order those chords which were at mid-span and near to the longitudinal centreline, yielded at first.

Temperatures in the furnace and at several points of the pre-stressed cable steel truss, as well as deformations, deflections and the stress changes of upper chord and the bottom steel cable and the change of displacement at different joint were measured to achieve those goals and, consequently, to assess the deformation behaviours and temperature of the pre-stressed steel cable.

This paper considers the extension of the force-based element formulation to simulate the nonlinear, temperature-dependent response of structural frames exposed to fire. The two-dimensional formulation presented here accounts for thermal expansion, temperature-dependent material properties, and residual stresses. The element utilizes a fiber discretization to simulate the gradual plastification of the section. Geometric nonlinearities are included through coordinate transformations of the corotational reference frame. Analyses of benchmark experimental tests demonstrate that the force-based element formulation is computationally stable and provides accurate results for structures exposed to fire. In addition, comparisons to traditional displacement-based elements indicate that the force-based element may offer improved computational efficiency because fewer elements are needed per member.

The purpose of this paper is to explore the synergies between post-end-of-life of building (PEoLB) concepts and operations to achieve sustainability.

A systematic literature review (SLR) was conducted using 65 articles published between 2006 and 2017, and it has been subjected to descriptive and thematic analysis.

The descriptive analysis revealed that the majority of the articles were about (60 per cent) PEoLB operations, followed by (23 per cent) PEoLB concepts. Only 17 per cent of the articles have dealt with PEoLB-related strategic approaches. The thematic analysis elaborated on the literature development; interrelationships between PEoLB concepts and operations; impediments of introducing sustainability on these operations, remedial measures and information-based strategic approaches to achieve sustainability. Based on the findings, a conceptual framework for sustainable PEoLB operations is proposed. Furthermore, four areas of potential future research are discussed.

This study presents a future research agenda including best practices to plan PEoLB operations and the development of optimisation models, risk management and information-based strategic approaches.

The proposed conceptual research framework triggers and nurtures potential pathways to introduce sustainable PEoLB operations under sound information flow. This could create a basis for future empirical studies in filling the identified gaps in literature. The framework could also assist practitioners in mitigating risks associated with transportation, storing and contamination of salvaged materials through enhanced information flow. In addition, the framework provides some managerial guidance to organisations seeking ways of establishing sustainability during reverse logistics (RL) operations.

This paper presents an SLR of an emerging area of research that encapsulates closed-loop supply chain through sustainable RL operations. The study highlights the interrelationships between PEoLB concepts and operations. It develops a robust approach to effectively manage the PEoLB operations underpinned by a sound information flow to facilitate sustainability.

The purpose of this paper is to investigate the relationship between bank-specific characteristics and profitability in European banking sector to find the role of internal factors in achieving high profitability.

A regression analysis is built on an unbalanced panel data set comprising 175 observations of 35 top European banks over the period 2009-2013. To this end, the empirical data are collected from Bankscope and a comprehensive set of internal characteristics is examined.

All the determinant variables included in the model have statistically significant impacts on European banks’ profitability. However, the effects are not uniform across profitability measures. Regression findings reveal that size and capital ratio are significant company-level determinants of bank profitability in Europe, while higher loan loss provisions result in lower profitability levels. Findings also suggest that banks with higher deposits and loans ratio tend to be more profitable but the effects on profitability are statistically insignificant in some cases.

This study has considerable policy implications, as the performance of the European banking sector depends on its efficiency, profitability and competitiveness. In view of these findings, some suggestions may be functional for bank regulatory authorities to intensify and sustain robustness and stability of the banking sector.

The results provide interesting insights into the characteristics and practices of profitable banks in Europe. Few econometric studies have empirically explored the determinants of bank profitability in Europe so far, even though similar studies have been conducted in several developed countries. Therefore, this paper tries to close an important gap in the existing literature improving the understanding of bank profitability in Europe.