INFLUENCE OF SINGLE AND SHORT-CYCLE LOADS ON THE MECHANICAL CHARACTERISTICS OF GLUE-LAIMED PINE WOOD MODIFIED WITH EPOXY RESIN

Abstract

Wood  is  a  natural  unique  material.  It  has  its  own  exclusive  physical  and 
mechanical properties. Wood has many advantages compared to other materials. It is used in virtually all industries. The structure and unique physical and mechanical properties allow it to be used in the manufacture of a variety of products. The aim of the work is to conduct experimental studies of glued pine wood modified with epoxy resin under the influence of single short-term and low-cycle loads, construct deformation diagrams, and establish strength and deformation indicators. The method of experimental research of untreated and modified glued pine wood under the action of single short-term and low-cycle loads in axial compression along the fibers is presented. The method of wood modification with epoxy resin has been improved. Modified and unmodified prisms were tested under single and low-cycle loads on a STM-100 testing machine under axial compression along the fibers. Experimental studies of untreated and modified glued pine wood under the action of single short-term and  low-cycle  loads  under  axial  compression  along  the  fibers  have  been  conducted.  Averaged deformation diagrams of modified and unmodified glued pine wood under single short-term and low-cycle loads have been constructed. According to the results of experimental studies, the ultimate strength  and  corresponding  deformability  of  untreated  and  modified  glued  pine  wood  were established, both under single short-term and low-cycle loads. Modification of glued pine wood with epoxy resin increases the ultimate strength by 1.27 times, while the deformability decreases by 1.05 times. The effect of low-cycle loads reduces the ultimate strength of untreated glued laminated timber by 1.06 times, while the deformability increases by 1.13 times. For modified wood, the same pattern is observed: the ultimate strength decreases by 1.07 times, while the deformability, in turn, increases by 1.08 times.