Timber truss systems are very efficient load-bearing structures. They allow for great freedom in design and are characterised by high material use in combination with a low environmental impact. Unfortunately, the extensive effort in design and production have made the manufacturing and application of these structures, in this day and age, a rarity. In addition, the currently mainly used steel gusset plates adversely affect the costs and environmental impact of the trusses. The authors’ goals are to optimise the design of timber trusses and to solely use wood for all building components. The two research areas, (1) optimisation of the truss geometry and (2) optimisation of the joints by using solely wood–wood connections, are addressed in this paper. The numerical optimisation strategy is based on a parametric design of the truss and the use of a genetic solver for the optimisation regarding minimal material consumption. Furthermore, first results of the tensile and compression behaviour of the chosen wood–wood connections are presented. The basic idea for the joints is to use a plywood plate as a connector, which is inserted into the truss members and fixed with wooden pegs. The housing of the new robot laboratory located at BOKU Vienna is considered a special case study for the research and serves as an accompanying example for the application of the research within the present paper.

The paper is dedicated to the numerical analysis of a single-step joint, enabling the prediction of stiffness and failure modes of both single- and double-step joints. An experimental analysis of the geometrically simplest version, the single-step joint, serves as a reference for the calibration of the subsequent finite element model. The inhomogeneous and anisotropic properties of solid timber make detailed modelling computationally intensive and strongly dependent on the respective specimen. Therefore, the authors present a strategy for simplified but still appropriate modelling for the prediction of local failure at certain load levels. The used mathematical approach is based on the linear elasticity theory and orthotropic material properties. The finite element calculations are performed in the environment of the software Abaqus FEA. The calibrated numerical model shows a good conformity until first failures occur. It allows for a satisfactory quantification of the stiffness of the connection and estimation of the force when local failure begins and is, therefore, recommended for future, non-destructive research of timber connections of various shapes.

1. In recent years, sustainable construction has gained significant attention, with an increasing awareness of the environmental advantages of using wood and wood-based materials (Forest Products L...

This article investigates the effect of different drilling forces on drill bit wear and their effects on drilling time within the context of the development of a drilling robot for on‐site construction applications. The study explores variations in three force levels (80, 120, 160 N), three directional orientations (upwards, downwards, horizontal), four drill bit diameters (8, 10, 12, 16 mm), and two concrete strength types (C25/30, C70/85). The findings indicate that while there is little divergence in drill bit wear across force levels, the influence of concrete strength is undeniable. Furthermore, drilling time increases, by 7 % to 11 % after 37.5 m drilling depth and up to 68% after 150 m depending on the drilling configuration. In conclusion, the study reveals a notable discrepancy between the progressive increase in drilling time and the relatively stable progression of drill bit wear, particularly in achieving code‐compliant boreholes.