Web buckling study of the behaviour and strength of perforated steel beams with different novel web opening shapes

This paper presents an experimental and analytical study on the behaviour of perforated steel beams with closely spaced web openings. Seven specimens including two typical cellular beams (i.e. circular web openings) and five perforated beams with novel web opening shapes were tested to investigate the failure mode and load strength of the web-post between two adjacent web openings. Fourteen numerical test specimens were developed and analysed by the finite element method and the results were compared with the full scale experiments. The effect of web opening spacing/web opening depth of web-posts was studied to investigate the effective ‘strut’ action of the web-post buckling. The effect of the web opening depth/web thickness was also studied to investigate the stability (slenderness) of the web-post subjected to vertical shear load. Two hundred and twenty-fine elastic-plastic finite element analyses were then employed in a comprehensive parametric study to propose an empirical formula which predicts the ultimate vertical shear load strength of web-posts formed from the particular web opening shapes. Perforated beams with standard circular, hexagonal and elongated web openings are mostly used nowadays. Various non-standard web opening shapes are introduced through this paper. These new pioneering web opening shapes improve the structural performance of the perforated beams when examined under the web-post buckling failure mode. In addition, the manufacturing procedure of these non-standard web openings show great advantage in comparison with the manufacturing way of the more popular perforated beams with circular web openings (i.e. cellular beams)

Daylighting: appraisal at the early design stages

For a building design team concerned with the quality of the internal environment of buildings the percentage area of glazing on a building facade is one of the most useful criteria for judging the building envelope as a modifier of climate at early design stages since it is at the window that the various environmental parameters (heat, light and sound) remain only minimally modified. The percentage area of glazing can be used to relate the numerous and often conflicting functions of the window such as the provision of daylight, summer time teperatures, sound insulation, energy efficiency and view satisfaction

A comparison of flexural strengths of polymer (SBR and PVA) modified, roller compacted concrete

This brief article aims to reveal the flexural performance, including the equivalent flexural strength of PVA (Polyvinyl Alcohol) modified concrete by comparing it primarily with that of SBR (Styrene Butadiene Rubber) concrete. This data article is directly related to Karadelis and Lin [6]

Catalytic pyrolysis of rice husk for bio-oil production

Catalytic pyrolysis experiments have been carried out on Brunei rice husk (BRH) to obtain bio-oil using a fixed-bed pyrolysis rig. ZSM-5, Al-MCM-41, Al-MSU-F and Brunei rice husk ash (BRHA) were used as the catalysts for the catalytic pyrolysis experiments and comparison was done to analyse the changes in the bio-oil properties and yield. Properties of the liquid catalytic and non-catalytic bio-oil were analysed in terms of water content, pH, acid number, viscosity, density and calorific value. The bio-oil chemical composition shows that ZSM-5 increases the production of aromatic hydrocarbons and light phenols, whilst Al-MCM-41 reduces the acetic acid production. The catalytic runs increased the calorific value and water content in the bio-oil, whilst viscosity, density and acid number is decreased

Effects of gender differences on the subjective perceived intensity of steering wheel rotational vibration based on a multivariate regression model

This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2009 ElsevierThe aims of this study were to determine equal sensation curves for hand-arm steering wheel rotational vibration and to investigate the effect of gender on the subjective perceived intensity of steering wheel hand-arm vibration. Psychophysical response tests of 40 participants (20 mates and 20 females) were performed using a steering wheel rotational vibration simulator using the category-ratio Borg CR10 scale procedure for direct estimation of perceived intensity. The test stimuli were sinusoidal vibrations at 22 third octave band centre frequencies in the range from 3 to 400 Hz, with acceleration amplitudes in the range from 0.04 to 27 m/s(2) r.m.s. Multivariate regression procedures were applied to the experimentally acquired data in order to establish a regression model expressing the Borg CR10 perceived intensity values as a function of the two independent parameters of the frequency and amplitude of vibration. The equal sensation curves suggested a non-linear dependency of the subjective perceived intensity on both frequency and amplitude. Females were found to provide higher Borg CR10 perceived intensity values than males (p < 0.05), particularly at the higher intensity levels above approximately 1.0 m/s(2) r.m.s and at the higher frequencies above approximately 20 Hz.Relevance to industry: For the manufacturers of steering systems and of other automobile components this study provides vibration perception curves and identifies the possible importance of gender towards the perception of vibration which arrives at the steering wheel. (C) 2009 Elsevier B.V. All rights reserved

Fire analysis of steel frames with the use of artificial neural networks

The paper presents an alternative approach to the modelling of the mechanical behaviour of steel frame material when exposed to the high temperatures expected in fires. Based on a series of stress-strain curves obtained experimentally for various temperature levels, an artificial neural network (ANN) is employed in the material modelling of steel. Geometrically and materially, a non-linear analysis of plane frame structures subjected to fire is performed by FEM. The numerical results of a simply supported beam are compared with our measurements, and show a good agreement, although the temperature-displacement curves exhibit rather irregular shapes. It can be concluded that ANN is an efficient tool for modelling the material properties of steel frames in fire engineering design studies. (c) 2007 Elsevier Ltd. All rights reserved

The effect of polyethylene glycol on shellac stability

The effect of polyethylene glycol (PEG) having amolecular weight of 1000 and 2000 on shellac stability has been investigated in this research. The shellac was shellac wax free, and the solvent was ethanol 96%. Shellac films were prepared by solventevaporationmethod. The stability of shellac was investigated using insoluble solid test, Fourier Transform Infra Red (FTIR), Thermogravimetry Analyzer (TGA), and Water Vapour Transmission Rate (WVTR). The results showed that stability of shellac decreased after heating at 125oC for 10,30,90,and 180 minutes, and storing for 1 month at 27 oC and 85 relative humidity (RH). PEG improved the stability, and the most stable effect was achieved through PEG1000

Recycled household ceramic waste in eco-efficient cement: a case study

The ceramic wastes can cause strong damage to the environment. In this article, the experimental study was concentrated on the pozzolanic activity of household ceramic waste and clay bricks waste. The possibility of the partial replacement of Portland cement blended with ceramic waste powder without further heating treatment in different ratios was analyzed. The ceramic waste powder was mixed in samples in various ratios. The evaluation of the ceramic waste powder was performed by grain-size analyses using Laser granulometry, XRD, XRF, Frattini test and strength activity index (SAI) method. The results indicate that the pozzolanic activity of household ceramic waste was higher than that of clay bricks waste. The 15% of HC powder addition could be a possible upper bound for an effective substitution and may also be very cost-efficient for industrial application.The authors acknowledge the National Natural Science Foundation of China: Grant 51578109, and Fundação para a Ciência e a Tecnologia (SFRH/BPD/22680/2005)