Standardized wooden system for timber internal tension simulation

Forest operations performed after natural disturbances occurrence can be highly dangerous due to the critical environmental conditions. Only specialised operators can address such challenging situations. However, the high-quality training activities needed to train forestry operators are not easily feasible in real conditions. The implementation of an engineering system that simulates the complex context of salvage tasks can be a valid solution to prepare operators in a controlled environment. The simulation of critical issues in the use of damaged forest areas, typically represented by logs subjected to a typical stress situation, such as tensile or compressive stress levels, will be carried out through the design of a mobile system for simulation of tensions in timber. The proposed solution aims to define a modular wooden structure to be realized with standard logs available at the logging site to be versatile and safe. The structure will be provided with sensors and load cells that will show the exact level of the stress applied to the logs during the cutting simulation. To this aim, computer analyses with finite element models have been conducted to design a solution that considers multiple parameters, such as log dimensions, tree species, maximum load bearing capacity of the structure and defines an optimal range of design solutions. The numerical procedure recreates the actual stress level developed in collapsed trees, or other unfavourable situations, which might lead to unexpected hazardous condition for the forest operator. The obtained structure must fulfil different requirements: low weight structure, in order to keep the realization, fast assembly/disassembly operations and assure a sufficient safety level according to typical design provisions of real structures. The results provided in this work show that the proposed technique has been accomplished and a first full-scale prototype has been realized and tested.