CHANGE IN WOOD STRENGTH UNDER STATIC BENDING AND COMPRESSION ALONG FIBERS IN THE PROCESS OF TREE GROWTH

Journal Title: Architecture and Engineering - Year 2017, Vol 2, Issue 1

Abstract

According to the basic principles of bionics, internal forces are formed in the tree trunk during its growth; these forces generate the strength and resistance of the tree to influence of wind loads and its own weight. When internal forces appear, the strength of wood cells starts developing. The inflow of nutrients is the most intense in the most strained parts of the trunk. The wood responds to external effects through increasing the thickness of cell walls, their density, the modulus of elasticity, etc. The central part of the trunk starts experiencing internal compressive stresses along fibers and tensile stresses dominate the peripheral areas. The paper substantiates the relationship between the size of the core zone and the stress-strain state of wood. Under effects of internal forces the wood is formed during the growth of a tree as an anisotropic material having different tensile and compressive strengths along and across fibers. The hypothesis on parabolic distribution of internal forces along fibers is described making possible both determining the dimensions of the core and sap zones, and establishing mathematical correlation between the ultimate stress limits of wood during compression along fibers and under static bending. This was proved in numerous experimental studies made by different Russian and foreign research groups. According to calculations given in the paper, the ratio of the ultimate stress limits of wood of various species under compression along fibers to the ultimate stress limits under static bending depends on the nature of distribution of internal forces along the tree trunk. Application of computer technologies makes it possible to use the results obtained to produce sawn timber having required strength indicators.

Authors and Affiliations

Vladimir Glukhikh

Keywords

Related Articles

EVOLUTION OF KREMLINS AS EVOLUTION OF RUSSIAN URBAN SETTLEMENTS

The Kremlin is considered to be the first stage of evolution of the urban settlement in the period of strengthening of the Russian centralized state. Five main functions of the kremlin were identified. By now, some funct...

Historical peculiarities of formation of small town of Shebekino structure

The article is dedicated to study of historical peculiarities which influenced the social and economic development and formation of the functional and planning structure of the small town of Shebekino of the Belgorod Reg...

STABILITY CALCULATION OF ROD ELEMENTS OF SOLID-WALL ARCHES BY THE FLEXURAL-TORSIONAL FORM

The work considers main, most significant scientific works on study of the stability of rods with the curved axis; the issue of the subject matter investigation is examined. A procedure for determining the spatial displa...

The phenomenon of the Saint Petersburg variant of the regular city

Saint Petersburg building development formed by the first third of the 19th century is under review. At that time the idea of regular city design was put into effect to the fullest extent. The most significant and specif...

MODELING FRACTURE OF REINFORCED CONCRETE STRUCTURES UNDER IMPACT

Introduction: The papers presents results of an integrated experimental and numerical study on behavior of reinforced-concrete beams under impulse loading. The beams under study had three layers. The upper and lower laye...

Download PDF file
  • EP ID EP352942
  • DOI 10.23968/2500-0055-2017-2-1-24-31
  • Views 125
  • Downloads 0

How To Cite

Vladimir Glukhikh (2017). CHANGE IN WOOD STRENGTH UNDER STATIC BENDING AND COMPRESSION ALONG FIBERS IN THE PROCESS OF TREE GROWTH. Architecture and Engineering, 2(1), 24-31. https://europub.co.uk/articles/-A-352942