Mechanical properties of azobé (Lophira alata)

The use of tropical hardwoods in structural applications requires knowledge of the mechanical properties. Even though long experience is available with the species azobé (Lophira alata), much of the current knowledge is based on tests performed on small clear specimens for bending, compression and shear. Since tropical hardwoods are used in structures with high economic value, a sound knowledge of the mechanical properties allows for better optimisation and for minimal use of raw material. Bending, compression and shear tests have been performed on material in structural sizes. Characteristic values show that in most loading cases the structural capacity of the material is distinctly higher than currently assumed in practice. The relationship between static modulus of elasticity and bending strength has been determined. The depth effect was shown to be less pronounced than for softwoods

TERRE project : interplay between unsaturated soil mechanics and low-carbon geotechnical engineering

The geotechnical construction industry is a major component of the overall construction sector and is strategically important in infrastructure development (transportation, flood and landslide protection, building foundations, waste disposal). Although industry and research in the overall construction sector have been investing significantly in recent years to produce innovative low-carbon technologies, little innovation has been created in geotechnical construction industry, which is lagging behind other construction industry sectors. This paper discusses the interplay between low-carbon geotechnical engineering and unsaturated soil mechanics based on the research carried out within the project TERRE (Marie Skłodowska-Curie Innovative Training Networks funded by the European Commission, 2015-2019,H2020-MSCA-ITN-2015-675762)

A Revealed Reference Point for Prospect Theory

Without an instrument to identify the reference point, prospect theory includes a degree of freedom that makes the model difficult to falsify. To address this issue, we propose a foundation for prospect theory that advances existing approaches with three innovations. First, the reference point is not known a priori; if preferences are reference-dependent, the reference point is revealed from behavior. Second, the key preference axiom is formulated as a consistency property for attitudes towards probabilities; it entails both a revealed preference test for reference-dependence and a tool suitable for empirical measurement. Third, minimal assumptions are imposed for outcomes, thereby extending the model to general settings. By incorporating these three features we deliver general foundations for prospect theory that show how reference points can be identified and how the model can be falsified

The Future of Quality Control for Wood & Wood Products

Abstract The basis for the derivation of settings for a grading machine is a comparison between destructive test data and data recorded by the machine. If the knots are part of the strength predicting model, the model covers the length effect in timber as it predicts the relatively lower strength for longer boards. This paper discusses the influence of the location of the maximum knot value on the performance of the machine. The maximum knot value between the inner load points is used for model derivation in approval bending tests. In practise, these machines do not only consider knots in the centre part of the board, but over the full length. Therefore, the indicating properties during deriving settings and during grading in practise differ from each other. The grading machine detects the largest knot value independent of the position along the length of the board; by means of this value the strength class is predicted. The influence of these differences is discussed. Finally, the effect on yield is shown