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This research was aimed at investigating the fire performance of LSF wall systems by using 3-D heat transfer FE models of existing LSF wall system configurations.

This research was focused on investigating the fire performance of LSF wall systems by using 3-D heat transfer finite element models of existing LSF wall system configurations. The analysis results were validated by using the available fire test results of five different LSF wall configurations.

The validated finite element models were used to conduct a parametric study on a range of non-load bearing and load bearing LSF wall configurations to predict their fire resistance levels (FRLs) for varying load ratios.

Fire performance of LSF wall systems with different configurations can be understood by performing full-scale fire tests. However, these full-scale fire tests are time consuming, labour intensive and expensive. On the other hand, finite element analysis (FEA) provides a simple method of investigating the fire performance of LSF wall systems to understand their thermal-mechanical behaviour. Recent numerical research studies have focused on investigating the fire performances of LSF wall systems by using finite element (FE) models. Most of these FE models were developed based on 2-D FE platform capable of performing either heat transfer or structural analysis separately. Therefore, this paper presents the details of a 3-D FEA methodology to develop the capabilities to perform fully-coupled thermal-mechanical analyses of LSF walls exposed to fire in future.

This paper aims to present the details of a study undertaken to develop an energy-based time equivalent approach to obtain the fire resistance ratings (FRRs) of light gauge steel frame (LSF) walls exposed to realistic design fire curves.

The energy-based time equivalent method was developed based on the performance of a structural member exposed to a realistic design fire curve in comparison to that of the standard fire time – temperature curve. The FRR predicted by the energy-based method for LSF wall configurations exposed to both rapid and prolonged fires were compared with those from fire design rules and finite element analyses (FEA).

The proposed energy method can be used to obtain the FRR of LSF walls in case of prolonged fires and cannot be used for rapid fires as the computed FRRs were higher than the results from FEA and fire design rules due to the influence of thermal bowing and its magnification effects at a high temperature gradient across the studs for rapid fires.

The energy-based time equivalent method was developed based on equal fire severity principles. Three different wall configurations were considered and exposed to both rapid and prolonged fires. The FRR obtained from the energy-based method were compared with fire design rules and FEA results to assess the use of the energy-based method to predict the FRR of LSF walls.

This paper presents the details of full scale fire tests of LSF wall panels conducted using realistic fire time-temperature curves. Tests included eight LSF wall specimens of various configurations exposed to both parametric design and natural fire curves. Details of the fire test set-up, test procedure and the results including the measured time-temperature and deformation curves of LSF wall panels are presented along with wall stud failure modes and times. This paper also compares the structural and thermal behavioural characteristics of LSF wall studs with those based on the standard time-temperature curve. Finally, the stud failure times and temperatures are summarized for both standard and realistic design fire curves. This study provides the necessary test data to validate the numerical models of LSF wall panels and to undertake a detailed study into the structural and thermal performance of LSF wall panels exposed to realistic design fire curves.

This paper aims to study the controlled release and synergistic effect of water-soluble polyvinyl alcohol (PVA) on phosphate corrosion inhibitor at the interface of thermal insulation cotton/carbon steel.

This study was carried out using a coating method, scanning electron microscopy, energy dispersive spectroscopy and AC impedance.

The single-phase phosphate particles were coated/adsorbed on the PVA film, which was formed on the fiber surface of corrosion inhibitor/PVA-impregnated rock wool sample. On the surface of Q235 steel, an effective protective film was formed by the corrosion inhibitor with partially dissolved PVA that can significantly increase the polarization resistance of corrosion reaction, and reduce the capacitive reactance of electric double layer. The rock wool impregnated with the phosphate corrosion inhibitor and 1.5 per cent PVA showed obvious controlled release and inhibition synergism.

The rock wool impregnated with the phosphate corrosion inhibitor and 1.5 per cent PVA showed the following advantages: the adsorption and release quantities of the corrosion inhibitor increased by 3.3 and 2.9 times, respectively; the release-adsorption equilibrium time increased from 2 to 6 h; and the corrosion inhibition efficiency increased from 61.55 per cent to 94.6 per cent.

Impelled by the urgency of the energy crisis, one of business management's newest disciplines is spreading into most industrial and governmental organisations. Energy management, in common with its more established counterparts, is rapidly developing its own litany and identity. It is estimated that there are now approximately 7,000 energy managers in the UK. They have their own publications, seminars and exhibitions; they are supported by a welter of government sponsored advisory services and they are courted by an ever increasing number of consultants and experts.

Cases of corrosion of metal coated on its inner surface with insulating materials are frequently encountered, particularly where the insulation has become damp. Since this problem first arose acutely, shortly after the introduction in this country of the first all‐steel railway carriages some 24 years ago, many attempts have been made to overcome the trouble. For a long time the mechanism of this kind of corrosion was in doubt. Some thought that the materials used, especially asbestos, were the prime cause. Various attempts were made to use non‐absorbent insulants or to waterproof the visible face of the insulation with a film of bitumen or the like.

The purpose of this research is using materials to improve the thermal insulation, and reducing the cost. A large amount of energy is consumed by masonary due to cooling and heating. Adding material with certain percentages to the building materials is one of the ways to improve the thermal insulation, and these additives should keep as much as possible the mechanical properties of the building materials. Carbon additives are one of commonly used materials to masonry materials. In spite of the many advantages of using carbon fibers and carbon nano tubes (CNTs) to the cementitious materials, they are very expansive and their thermal conductivity is high.

In this research charcoal (which is a product of burning process) with very low thermal conductivity and cost in the form of micro particles will be used with mortar and compared with short carbon fibers and multiwall carbon nanotubes (MWCNTs) via thermal conductivity, density and compressive strength tests. This research includes also an effort to build a model of building to evaluate the thermal insulation of the materials used in the practical part. The main building design and performance simulation tool in this research is DesignBuilder.

Results showed that adding micro charcoal particles to mortar resulted in improving the thermal insulation and decrease the rate of reduction in the compressive strength compared to other additives, while adding short carbon fibers resulted in improving the thermal insulation and decrease the compressive strength. Adding MWCNT to the mortar had a negative effect on mechanical and physical properties, i.e. compressive strength, density and thermal insulation.

This paper uses DesignBuilder software to design a model of building made from the materials used in the practical part to predict and evaluate the thermal insulation.

Whilst the overall need to conserve energy is generally accepted, the importance of undertaking a detailed survey before the start of any insulation work in existing buildings is seldom recognised.

Surveyors, who may be involved in specifying retro‐fitted cavity insulation, need to know the key factors which influence the potential risk of rain penetration. Proposes guidance for surveyors to undertake a low‐cost initial visual survey and desk study as a first stage in the assessment of a dwelling′s suitability for retro‐fitted cavity insulation. A case‐study of low‐rise housing on a local authority estate on the south coast of England, which has retro‐fitted cavity insulation, allowed the identification of these key factors and testing of their statistical significance. Factors identified are aspect towards prevailing wind and driving rain index; exposure (related to local topographic and sheltering features); wall impermeability; and any factors of particular significance to the site. If an individual dwelling has a combination of these factors, it is likely to have a 60 per cent increased risk of rain penetration.

Our previous paper on this subject in Structural Survey (Vol 3 No 1) outlined the problems facing the surveyor in this difficult area. Clients may often expect (sometimes implicitly) surveyors to identify hazardous materials as part of their normal survey procedure and subsequently to assist in the assessment of any hazard to the occupiers, with the selection of alternative materials, and advise upon the pros and cons of remedial or replacement work. While the paper identified the locations where hazardous materials may be expected in domestic buildings, many questions on the other issues remain unanswered.