The explosion process of explosives in a borehole applies a very high pressure on its surrounding rock media. This process can initiate and propagate rock fractures, and finally, may result in the rock fragmentation. Rock fragmentation is mainly caused by the propagation of inherent pre-existing fractures of the rock mass and also from the extension of the newly formed cracks within the intact ...

Softwood logs are processed into green boards through a series of horizontal or vertical sawing operations that reduce lumber thickness. This paper uses physical understanding to model how systematic and random errors in board thickness accumulate during sequential resawing. The error model is validated on board thickness measurements gathered at a northern California sawmill. The analysis • ex...

A versatile microcomputer-based interactive graphics sawing program has been developed as a tool for modeling various hardwood processes, from bucking and topping to log sawing, lumber edging, secondary processing, and even veneering. The microcomputer platform makes the tool affordable and accessible. A solid modeling basis provides the tool with a sound geometrical and topological foundation....

Studying the cutting temperature is critical for unlocking secrets of sawblade wear, lifespan, and metallurgical alterations beneath surface. This paper describes an investigation into 45 steel during dry sawing, using a cemented carbide circular saw blade under various conditions. A acquisition system was developed, enabling determination average arc zone in workpiece sawtooth tip via semi-aut...

A 3D log sawing optimization system was developed to perform log generation, opening face determination, sawing simulation, and lumber grading using 3Dmodeling techniques. Heuristic and dynamic programming algorithms were used to determine opening face and grade sawing optimization. Positions and shapes of internal log defects were predicted using a model developed by the USDA Forest Service. L...

Although Pinus sylvestris L. is the most frequently analyzed wood species with respect to cutting forces in sawing experiments, the problem of prediction of reliable values of tangential FC and radial FN cutting forces for specific sawing conditions, according to the method employing a specific cutting resistance K (N·mm) and correction coefficients CR, C, C, CAP, CVC, CMC, CT, as expressed b...

Instituto de Tecnología de Productos Forestales, Facultad de Ciencias Forestales y de Recursos Naturales, Universidad Austral de Chile, Valdivia. Chile. aguilera@ uach.cl Instituto de Acústica, Facultad de Ciencias de la Ingeniería, Universidad Austral de Chile, Valdivia. Chile. [email protected] Corresponding author: [email protected] Received: 24.05.2010. Accepted: 26.08. 2010. SOUND PRESSURE AS...