Study of the mechanical properties of coniferous wood of different ages at standard humidity

Experimental studies of age effect on the strength and deformation characteristics of coniferous wood of standard humidity on compression along the fibers under a strain-controlled mode were carried out. Valid diagrams «stress σ с – deformations u c » were plotted from the beginning of loading to the failure (ascending and descending branches). The full range of strength and deformation parameters was determined experimentally, both on the ascending and descending branches of the deformation diagram. It was established that the values of ultimate strength, critical and final deformations, and elasticity modulus slightly decrease from 60 to 40 years and significantly from 40 to 20 years. In particular, the average values in the range 60 to 20 years decrease for ultimate strength by 26.5-35.4%; critical deformations – 19.8-28.7%; final deformations – 18.0-24.7%; elasticity modulus – 13.1-17.0%.