( , 14 16 2008 . )

PROCEEDINGS

SCIENTIFIC PAPERS

SCIENTIFIC-TECHNICAL CONFERENCE

INNOVATION IN WOODWORKING INDUSTRY AND

ENGINEERING DESIGN

( Yundola, 14-16 November 2008 )

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ISBN 978-954-323-538-4

, 2009

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1.

- 2007-2030 .............................9 2.

- .......................................................12 3.

CFRP - Katerina Novosseletz, Jozef tefko, Jn Sedliaik ...............................15 4.

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CONTENTS: 1. ABOUT NATIONAL RESEARCH AGENDA 2007-2030

RUSSIAN FOREST-BASED SECTOR - Valentin Shalaev..................................................9 2. INNOVATIONS IN EUROPEAN EDUCATIONAL PROGRAMS - Veselin Brezin .....12 3. TIMBER CONSTRUCTION REINFORCED

WITH CFRP LAMELLAS - Katerina Novosseletz, Jozef tefko, Jn Sedliaik .................15 4. FACTOR EFFECTS IN THE APPLICATION OF ADEQUATE MODELS

FOR LOG SAWING - Georgi Blagoev .................................................................................19 5. WATER AND WATER-VAPOUR SORPTION OF SCOTS PINE WOOD

IMPREGNATED WITH SILICEOUS SUBSTANCES - Christofor Videlov....................26 6. STUDY ON THE ABNORMAL HEARTWOOD

OF ROUND WOOD - Genka Bluskova, Nikolay Bardarov, Marina Naydenova .................29 7. WOOD STRUCTURE OF CAUCASIAN WHORTLEBERRY (VACCINIUM

ARCTOSTAPHYLOS L.) Genka Bluskova, Aleksander Tashev, Nikolay Bardarov .......33 8. STUDY ON THE WOOD STENOSIS OF SCOT PINE, OAK,

WALNUT, BEECH AND DABEMA - Nikolay Bardarov....................................................36 9. DETERMINATION OF SOME ANATOMICAL INDICES

OF CONIFEROUS TREE SPECIES - Nikolay Bardarov ...................................................41 10. DEFORMATIONS AND RHEOLOGYCAL PROPERTIES

OF WOOD - Ekaterina Trichkova Vetova...........................................................................46 11. WOOD POTENTIAL AS AN ORGANIC PRODUCT - Ivan Genov ................................50 12. POTENTIALITIES AND ADAPTATION OF CNC WOODWORKING CENTERS -

Bojidar Dinkov, Peter Savov, Nikolina Ilkova, Marina Mladenova, Viktor Savov.................53 13. COGENERATION TECHNOLOGIES FOR USING

WOOD BIOMASS - N. Yossifov, L. Takeva, M. Stoyanova ................................................62 14. DETERMINATION OF RAW-MATERIAL PREHEATING TIME AT

THERMO-MECHANICAL PULPING OF WOOD - Viktor Savov, Liliana Takeva........67 15. HEAT TREATED WOOD PRODUCTION, PROPERTIES,

APPLICATIONS - George Sheytanov, Veselina Nedyalkova...............................................72 16. RESEARCH ON THE KINETICS OF THE SORPTION AND

THE DEGREE OF THE WATER-RESISTANCE OF THE FIBRE BOARDS WITH MEDIUM DENSITY AND SPECIAL PURPOSE - Lilliana Vallcheva.................80

17. P0SSIBILITIES OF UTILIZATION OF CORC REFUSE FROM CORK-STOPPERS MANUFACTURING - Todor Todorov, Bojidar Dinkov....................85

18. A STUDY OF THE PRESSURE AND FRACTION CONTENT IMPACT ON SUNFLOWER STALK BRIQUETTE DENSITY AND TRANSVERSE STRENGTH - Rosen Grigorov ...................................................................89

19. MECHANICAL PROPERTIES OF THREE-LAYERED BOARDS WITH DIFFERENT KIND OF LOGNOCELLULOSIC AGRICULTURAL RESIDUES IN INTERMEDIATE LAYER Julia Mihailova, Borce Iliev, Todor Todorov, Rosen Grigorov .............................93

20. SCOPE OF THE ERGONOMIC DESIGN PRINCIPLES, ESTABLISHED IN THE BDS EN 614-1:2007 IN IMPLEMENTATION - Lillyana Vallcheva, Svetla Vassileva, Sofia Anguelova, Iskra Yoshovska .............................99

21. OPTIMISATION OF THE RESOURCE STRUCTURE OF THE ROUND WOOD MATERIAL IN TIMBER COMPANY Nikolay Neykov........103

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22. METHODICAL PROBLEMS OF MARKET RESEARCH IN WOODWORKING AND FURNITURE INDUSTRY - Diana Ivanova......................107

23. INTEGRATIVE AND FLEXIBLE PRODUCTION SYSTEM THE MARKS OF THE NEW FORM OF ORGANIZATION OF THE PRODUCTION - Nikola Grigorov.......................................................................113

24. INVESTIGATION ON FOREST POTENTIAL OF REGIONAL FOREST DISTRICT PAZARDZHIK - Ivan Petrov Paligorov, Ivaylo Hristov Ivanov, Elena Milan-Krigan Velichkova ..................120

25. STUDYING OF COMPETITIVENESS OF THE FURNITURE ENTERPRISES IN BULGARIA - Diana Ivanova, Nikolay Stoenchev, Stanislava Kovacheva, Ivaylo Ivanov ..........................126

26. ON THE PROOF OF MAXIMUM LIKELIHOOD ESTIMATORS OF PARAMETERS IN A MULTIVARIATE NORMAL DISTRIBUTION - Dimitrinka Ivanova Vladeva ..............................................131

27. SIMULATIONS IN TWO QUEUEING SYSTEMS WITH REPEATED CALLS - Velika Dragieva ..................................................................134

28. INNOVATIONS IN TEACHING STRENGTH OF MATERIALS: ON THE PROOF AND APPLICATION OF CASTIGLIANO THEOREM - Stefan Stefanov....................140

29. NEED ANALYSIS FOR TRAINING IN OCCUPATIONAL SAFETY IN WOOD INDUSTRY - Petar Antov, Tanya Pancheva ....................................144

30. RECKONING OF HYDRAULICS RESISTANCES BY THE METHOD OF AN EQUIVALENT LENGTHS - Bojidar Dinkov, Nikolina Ilkova ............................148

31. PECULIARITIES AND EFFICIENCY OF CONVEYERS IN WOODWORKING AND FURNITURE ENTERPRISES - Bojidar Dinkov, Nikolina Ilkova .........................150

32. RATIONAL UTILIZATION OF ELECTRICAL TOOLS IN WOODWORKING AND FURNITURE MANUFACTURE - Hristo Mihailov, Peter Savov, Viktor Savov ....155

33. MODEL BASED AUTOMATIC CONTROL OF HEAT AND MOISTURE TRANSFER INSTALLATIONS IN THE WOODWORKING INDUSTRY - Nencho Deliiski ............................................161

34. IDENTIFICATION OF THE TYPICAL DEFECTS OF THE DRIVING MECHANISM OF CARVED VENEER MACHINES USING VIBRODIAGNOSTICS - Georgi Vukov, Boicho Marinoff ..................................166

35. CIRCULAR SHAFT RIGIDITY CALCULATION METHOD - Hristo Mihailov .........170 36. PARAMETRICAL MODELING OF A SHAFT

FOR CIRCULAR SAW WITH SOLID WORKS Nelly Staneva ..................................173 37. PNEUTRANSPORT INSTALLATION COLLECTOR TYPE

WITH FLATTING PIPE - Peycho Myrvekov1, Lachezar Nikolov ...................................178 38. METHOD FOR DIMENSINING OF THE RAILWAY

OF THE FORE BRIDGE IN FRONT OF THE AUTOCLAVE Part 1. METHOD FOR DIMENSIONING OF THE RAILS - Slavcho Sokolovski .......183

39. METHOD FOR DIMENSINING OF THE RAILWAY OF THE FORE BRIDGE IN FRONT OF THE AUTOCLAVE Part 2. METHOD FOR DIMENSIONING OF THE TRAVERSE - Slavcho Sokolovski..............................190

40. METHOD FOR DIMENSINING OF THE FORE BRIDGE OF THE AUTOCLAVE Part 3. METHOD FOR DIMENSINING OF THE SUPPORT FRAME - Slavcho Sokolovski...........................................................195

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41. INVESTIGATION ON THE WORKING CAPACITY AND THE QUALITY OF BAND SAW BLADES WITH SETTING TEETH FOR BAND SAW MACHINES WITH CARRIAGE AND FOR HORIZONTAL MOBILE BAND SAW MACHINE - Zhivko Gochev Petar Nikolov ....201

42. THEORETICAL DISTRIBUTION OF THE INTENSITY OF FAILURE OF THE MACHINES - Georgi Tasev........................................................206

43. CALCULATION OF THE RELIABILITY OF MACHINES IN AN UNKNOWN LAW OF DISTRIBUTION OF THE FINAL PROCESSED PRODUCT - Georgi Tasev........209

44. SPECIAL FEATURES OF CREATING OF WOOD SCREW 3D MODELS WITH SOLID WORKS - Nelly Staneva ...................................................212

45. THEORETICAL RESEARCH ON THE LOADING CAPACITY OF DOOR FLAP STAYS FOR FURNITURE - Assia Marinova, Vassil Jivkov ....................217

46. STUDY FOR DETERMINING OF THE RELATION BETWEEN CURVES RADIUS AND PRESSURE OF SOLID WOOD UPON BENDING OF FURNITURE PARTS - Dimitar Angelski.................................................222

47. INVESTIGATION OF SORPTION OF THERMALLY TREATED WOOD - Panayot Panayotov, Jivko Georgiev ..................................................225

48. INTERNAL STRESSES IN WOOD OF CONIFEROUS TREE SPECIES DRIED IN SOLAR KILN WITH SIMPLE CONSTRUCTION - Ralitsa Simeonova ..................230

49. ADHESION AND HARDNESS OF COATINGS FORMED WITH ACRYLIC EMULSION ON WOOD AND MDF - Panayot Panayotov, Rumyana Bonova.................234

50. INFLUENCE ON QUANTITY OF THE PIGMENTS ON THE ADHESION AND THE HARDNESS OF OPAQUE COATS FORMING WITH ACRYLIC PAINTS - Rumyana Bonova..............................240

51. SEATING FURNITURE IN MODERN DWELLING EXPERIMENT WITH MATERIALS, TECHNOLOGIES AND CONCEPTS - Desislava Angelova .....245

52. THE VERTICAL GARDENS AN ALTERNATIVE OF THE TRADITIONAL INTERIOUR PHYTODESIGN - Mariela Marinova, Veselin Shahanov ...........................253

53. SOME ASPECTS OF THE UPHOLSTERED FURNITURE DESIGN PROCESS - Yancho Genchev......................................................259

54. STIFFNESS COEFFICIENTS UNDER BENDING TEST OF T-SHAPE CORNER JOINTS OF FRAME STRUCTURAL ELEMENTS MADE OF SWEET CHESTNUT WOOD - G. Kyuchukov, G. Gruevski, A. Marinova, B. Kyuchukov...................................265

55. PUBLIC BUILDINGS AND DISABLED PEOPLE - Elena Pissareva.............................271 56. ENVIRONMENT OF DISABLED PEOPLE PROBLEMS

AND REQUIREMENTS - Elena Pissareva .........................................................................276 57. COMPOSITION PRINCIPLES FOR ACHIEVING

GRAPHIC EXPRESSIVENESS TROUGH EXPERIMENTATION WITH FUNCTIONAL OLJECTIVE SYMBOLS - Lyubomir Gurinov...........................281

58. ECODESIGN AS A FACTOR FOR SUSTAINABLE FURNITURE PRODUCTION - Katinka Mihova, Tsvetelina Simeonova .........................287

59. FUNCTION IN PRODUCT DESIGN IN THE CONTEXT OF SEMIOTICS - Miroslava Petrova...............................................291

60. FUNCTION AND FORM IN INDUSTRIAL DESIGN - Miroslava Petrova ...................297

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ABOUT NATIONAL RESEARCH AGENDA 2007-2030 RUSSIAN FOREST-BASED SECTOR

Valentin Shalaev* Moscow State Forest University, Russia

Forest is the largest biome and a single country in Northern Eurasia Russia is holding 20,5% of global forest resources (FAO 2005). Area of the Rus-sian forests is about 808,8 millions ha. Wood volume in forests is about 80,5 milliards m3 (99,5 m3/ha). Bo-real and temperate forests amount altogether to about 50% of global boreal and temperate forests. Russian forest accounts for 30% of raw materials in the world market. Russia holds 26% of the worlds pristine for-ests. The Russian forests play an important role in the global climate system; they are gigantic oxygen fac-tory, global reservoir of the organic matter, powerful regulator of energy fluxes and water cycle. Forests are biotope for wild animals and a natural habitat envi-ronment for indigenous populations. It is difficult to overestimate the role of forests as a source for many goods of vital importance for human society. In the long run, it will not be economically justifiable to manufacture other than higher value-added products. For sustainable development a more knowledge- based, more customer-focused and more innovation oriented forest industry should be built. The objectives of National Research Agenda (NRA) of the Russian Forest-based Technological Platform are following: Promote development of the Russian forest-based sector, including: sustainable forestry, pulp and paper industry, wood products, bio-energy, green chemicals and composites; Contribute to more efficient research and education and training in forest - based sector; Improve the level of innovation; Stimulate increased research funding and utilise the possibilities of different national and international fi-nancial funds and programmes. The Strategic Research Agenda (SRA) of the Euro-pean Forest-based Technological Platform (FTP) had identified 26 priority research areas whereas the Rus-sian NRA chose 19 of them as the most relevant to fit the Russian Forest-based sector issues. Priority research areas in the Russian NRA referring to the SRA strategic objectives defined by the Euro-pean FTP are as follows. Strategic objective 1: Development of innovative products for changing markets and customer needs 1-5: Building with wood 1-6: Commercializing soft forest values 1-7: Moving Europe with the help of bio-fuel

1-8: Pulp, energy and chemicals from wood bio-refinery 1-9: Green specialty chemicals 1-10: New generation of composites Strategic objective 2 Development of intelligent and efficient manufactur-ing processes, including reduced energy consumption 2-1: Reengineering the fibre-based value chain 2-2: More performance from less inputs in paper products 2-3: Reducing energy consumption in pulp and pa-per mills 2-4: Advanced technologies for primary wood proc-essing 2-6: Technologies to boost heat and power output Strategic objective 3: Enhancing availability and use of forest biomass for products and energy 3-1: Trees for the future 3-2: Tailor-made wood supply 3-3: Streamlined paper recycling 3-4: Recycling of wood products a new material resource Strategic objective 4: Meeting the multifunctional demands on forest re-sources and their sustainable management 4-1: Forests for multiple needs 4-2: Advancing knowledge on forest ecosystems 4-3: Adapting forestry to climate changes Strategic objective 5: The sector in a societal perspective 5-3: Citizens perception FORESTRY Vision. The key principle of modern policy is the sus-tainable development of multifunctional forestry. The Russian forest-based sector aims at sustainable forest management, multiple use of forests taking into con-sideration their global ecological significance, safe-guarding biodiversity and forest ecosystem functions. The priority areas in NRA are development of sus-tainable forestry management systems adapted to lo-cal and regional conditions, forest inventory, forest monitoring of current changes, national certification strategy to enhance the value of forest resources and services, commercializing soft forest values, adapting forestry to climate change. Goal: Developing sustainable and multifunctional forestry.

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Main Research Areas: Forest ecosystem reactions on environmental changes; Forest biodiversity and ecosystem functions evalua-tion; Forests for multiple needs; Forest reproduction; Forest protection; Forest monitoring: ground-based and remote sensing methods; Adapting forestry to climate changes; Sustainable management of forest in the context of global changes. WOOD PRODUCTS Vision. Russian forest resources are not enough used for wood products manufacturing due to a number of reasons, one of which is deep institutional transforma-tion of wood based sector of economy which has not finished yet. Almost all wood products have a con-sumer demand far exceeding the possible supply and consequently a good economic environment for pro-duction development. The latter can easy achieved in a modern technological and management background with the participation in international cooperation and attraction of foreign intellectual and financial invest-ments. Russia is now world fourth in wood harvesting now. Meanwhile its share in the world global exports of wood and paper products is only 2.3%. By the year 2030 this situation should be changed. Goals: Creation of technological, management and planning environment for faster development of wood process-ing industry; Diversification of wood products variety and rising their quality to make them more attractive for industry and private consumers; Facilities development for environmentally friendly and economically efficient complex use of the whole trees biomass including leafs and needles. Main Research Areas: Research of the properties of larch wood and sub-stantiation of processing technologies; Research of properties and a substantiation of tech-nologies of wood products from aspen; Substantiation of a continuous not destructive qual-ity monitoring in the building of wooden construc-tions; Development of technologies for surfaced OSB and surfaced MDF production; Modeling and optimization of sawing, heating and pressing operations; Optimization of power expenses in the woodwork-ing enterprises using waste wood; Development of technology for manufacturing fuel pellets using waste wood; Widening of the range of prefabricated wooden houses for human wellbeing and welfare, especially for rural areas.

PULP& PAPER PRODUCTS Vision. Pulp and paper industry is a basis for sustain-able development of the entire Russian forest-based sector. Fast growth of the domestic market, competi-tiveness in the world market as a producer of northern reinforcing fibers and paper-board production on the basis of the virgin fibers are nowadays the characteris-tics of the Russian pulp and paper industry, based on the of the world forest resources. The long-term lack of the new pulp and paper enterprises opens up new vistas for implementation of the innovation tech-nologies in Russia. Goal: Creation and implementation of the innova-tional model of the Russian pulp and paper industry development. Main Research Areas: Implementation of biorefinery concept: 1- for the production of chemicals and bio-fuels alongside with pulp production; 2- for different forest residues, bark and woody wastes of mechanical and chemical proc-essing, not integrated in pulp production; 3- for the stage by stage reconstruction of existing pulp and pa-per enterprises; Improvement of production structure for semi-manufacture fiber products with increased output of the knowledge-intensive products, widening the use of recycled materials (wastepaper) and mineral fillers in paper and cardboard production; Reduction of industrial loads of deep chemical wood processing to account for waste and byproducts of the main manufacturing process converted to raw materi-als for other technological processes; Influence of environmental factors (natural distur-bances, anthropogenic effects, climate changes) on wood structure and its further processing; Energetic use of different forest residues and by-products from mechanical and chemical fiber process-ing; The use of woody raw material and its products for decontamination and recultivation purposes; Reduction of environmental impact of the pulp and paper mills; New generation of cellulose composites. BIOPRODUCTS SPECIALTY CHEMICALS and COMPOSITES FROM FOREST- and HU-MUS-BASED BIOMASS Vision. The forest-based sector has a key role in find-ing environmentally friendly solutions for manufac-turing platform and specialty chemicals and compos-ites. Bioproducts have a central role in restructuring the market of petrochemicals, in securing varied feed-stocks for chemical industry, in increasing safety of the chemical products and minimizing dangerous wastes upon raw materials handling and processing. Wood, wood waste, and humified materials provide for rich biogenic raw resources. Large quantities of different types of base or platform chemicals can be isolated or produced from wood, wood wastes, and organic rocks. Wood wastes include those produced

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during mechanical, chemical, enzymatic, thermal and other processing, including multitonnage pulping spent liquors and bioethanol production residues as well as different types of forest residues in bio-refineries. Humified materials include peat, sapropel, leonardite, composts, activated sludge, and others. Upgrading the organic constituents of these materials to value-added specialty chemicals opens an opportu-nity for creating new types of forest-based value chains and development of market for products sus-tainable from economical, environmental and social aspects. This would significantly reduce societys de-pendence on oil-derived chemicals and materials. Goal: To develop innovative products from wood-, other plant-, and humified biomass, competitive on the future lead market of bioproducts Main Research Areas: Alternative feedstocks for chemical industry through combined treatment of wood, other plant, and humi-fied biomass using biorefinery and chemical process-ing; Specialty chemicals from wood, other plant, and humified biomass; Composites from wood, other plant, and humified biomass. BIOENERGY Vision. Bioenergy is an important integral part of the modern principles of sustainable forest management. It is evident that Russian forests have a huge bio-energy potential. It comes from logging, sawing and woodworking wastes, low-quality wood from sanitary logging etc. For example, the wood waste in the ply-wood industry is up to 60%. In todays Russia the bulk of this biomass is left in the forest, burnt or bur-ies at disposal sites. Beside capital-intensive produc-tion of advanced construction materials, this wood waste should be used for energy: (1) energy produc-tion for the local purposes, implying CO2 emissions reduction and (2) production of refined biofuels (pel-lets, briquettes, chips) for the open market, including export to EU countries. The general energy potential of the unused biomass in different value-chains of the Russian forest-based sector has never been subjected to a thorough systematic research; it is necessary to work out a development strategy for co-operation in this field. The key challenge of the research in bio-energy potential is to investigate the limit and avail-ability of wood waste and non-industrial wood for biofuel production and the potential of CO2 reduction in the framework of fuel-switch projects from oil and coal to biofuel. Goal: Search and selection of strategic approaches to bio-energy development. Main Research Areas: Production of solid, liquid and gaseous biofuel; Energy as a result of wood biorefinery; Technologies for significant increase of heat and power output.

EDUCATION and TRAINING Vision. Skills and knowledge is the basis for the strengthening the competitiveness of the forest-based sector and contributing to the improvement in the quality of life of modern citizens. R&D are the main instruments to achieve these strategic goals. Increas-ing demand in continuing education in all sectors of economy in conditions of the fast growth is one of the most important and challenging goals of current EU and Russian policy. For the intensification of forest information exchange and research for sustainable forest management in Russia, the Moscow State For-est University will establish a regional support net-work in Russia. This center will be a foundation for coordinating the activities of the higher education institution, scientists and teachers, the representatives of business, and state institutions and organizations to assure quality and development of the higher vocational education, as well as to forecast the promising directions and de-velop scientific and methodological support for train-ing the specialists in forest science, engineering and technologies. In addition, it will serve to open up the huge wealth of information and experience to the wider world and increase partnerships with other countries and international organizations in this field. Goals: Providing the conditions to meet the demands of citizens, society and a labour market with high quality education; Integration into a uniform European scientific and educational space; Developing the system of continuous education in Russia in close connection with the market demand. Main Research Areas: Research and development in close cooperation with the business sector; Working out proposals for the structure and scope of the main educational programs advanced vocational education in the field of forest-based sector, certifying the educational process; Prosperous, new and significant business area based on the highest level of R&D knowledge; Development and demonstration of processes for continuous learning and training; Development and demonstration of technologies for producing special courses; Development and demonstration of the required new distribution infrastructure for stakeholders.

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TIMBER CONSTRUCTION REINFORCED WITH CFRP LAMELLAS

Katerina Novosseletz1, Jozef tefko2, Jn Sedliaik3 Technical University in Zvolen, e-mail: 1knovosseletz@yahoo.com, 2stefko@vsld.tuzvo.sk,

3janos@vsld.tuzvo.sk

SUMMARY In this study we are discussing the possibility to use new materials like Fibre Reinforced Plastics (FRP) for reinforcement of wood constructions. The particular focuses are on the possibility to bond together Carbon Fibre Reinforced Plastics (CFRP) with wood and to improve mechanical properties of glulam beams. The experimental part includes the basic shear test of the glued line CFRP lamellae-wood and the tests of the mechanical properties of the reinforced glulam beams. Keywords: CFRP, wood, glue, CFRP-reinforced glu-lam, mechanical properties 1. INTRODUCTION Reinforcement is used to economical utilize wood ma-terials for production of glulam keeping its reliability and high utility. Structural members are reinforced by different materials steel, glass fibres, polyethylene fi-

bres and in the present by highly effective carbon lamellas CFRP (Carbon Fibre Reinforced Plastics). CFRP are used in the building structures with differ-ent material basis concrete, ferroconcrete and also wood, however in not such extent. Requirements of beams strengthening:

- requirement of increasing of carrying capacity of structures due to change of loading

- additional strengthening of load elements of original wooden constructions at restoration

- elimination of wood creep, which is observed by increasing of deflection of beam in time depend-ence

- strengthening of wood structure elements for which structural high of cross-section is limited.

The most important factor is E-modulus. In the table 1 are given basic characteristics of wood and some ma-terials used for reinforcement of the building units.

Tabal 1: Characteristics of materials

2. MATERIALS 2.1. GLULAM BEAMS The evaluation of the flexural strength of reinforced and non-reinforced glulam beam was the main topic of this study. Glulam or glue-laminated timber, intro-duced in Europe in the late 19th century, consists of sawn lumber laminations bonded with an adhesive so that the grain of all laminations runs parallelly with the long direction. 2.2. FIBRE REINFORCED PLASTICS (FRP) Reinforced plastic is the generic term used to describe specific plastic materials reinforced with high strength fibres. The plastics are most often epoxy, but other plastics, such as polyester, vinyl ester or nylon, are also sometimes used. The most suitable fibres for strengthening applications are glass, carbon and ara-mid. The FRP reinforcement is available in two basic forms: sheet material or fibres pre-impregnated with resin. The selection of the appropriate fabrics depends on the application. The lamellas have many advantages:

- corrosion resistance - very high strength - excellent durability - low specific gravity - no limited length - transport in the form of coil - high modulus of elasticity - chemical stability - flexibility 2.3. ADHESIVE The first step to make good bonding of wood - carbon lamellae is a choice and characteristic of appropriate adhesives. Reinforcement of wood with carbon lamel-las is performed by synthetic adhesives which are of-ten used in practise and allow gluing of the glulam beams in one cycle:

- Polyurethane adhesive (PUR) - JOWAPUR 686.60

- Resorcinol-formaldehyde resin (RF) - Cascosi-nol 1711 with hardener 2622

Reinforcement material Building material Characteristics CFRP Steel lamellas Wood Tensile strength [MPa] 2 400 235 110

E-modulus [MPa] 165 000 210 000 10 000

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- Melamine-formaldehyde resin (MEF) - Cas-comin 1250 with

3. EXPERIMENTAL TESTS The experimental tests were divided into three main groups:

- bending tests on long-span beams - examination of the mechanical properties of

wood used for experimental beams production - glue tests

3.1. BENDING TESTS ON LONG-SPAN BEAMS

For the experimental tests were made long-span beams with subsequent parameters:

- dimensions of the glulam beams: 160 x 440 x 9250 mm

- 11 spruce lamellas - carbon lamellas Sika CarboDUR S512, width 50

mm, thickness 1,2 mm, E = 165 000 N/mm2 - melamine-formaldehyde resin (MEF) - CASCO

NOBEL, - polyurethane resin (PUR) - (PUR) JOWAPUR

686.60

Figure 1: Scheme of loading of the long-span beams

Figure 2: Non reinforced beam after destruction and way of scanning of the deformation

Figure 3: Scheme of the cross-sections of the tested long-span beams

16

For the experimental test were made five different al-ternatives: K - control beam without reinforcement, 1- CFRP lamellae over the lower wood lamellae, 2 - double reinforcement between the wood lamellas, 3 - on the bottom of the beam, 4 - double-sided rein-forcement. The reinforcement width was 50 mm with the exeption of the alternative 1, where 3.2. MECHANICAL PROPERTIES OF WOOD The following testing procedures were performed:

- static bending by DIN 52 186 - compression parallel to grain by DIN 52 185

- compression perpendicularly to grain by DIN 52 192

- shear parallel to grain by DIN 52 187 - tension parallel to grain by DIN 52 188

The average mechanical properties of the local wood are as follows:

- modulus of elasticity 3.3. GLUE TESTS We performed the following testing procedures: - shear strength by STN EN 205

Figure 4 Scheme of tested samples by STN EN 205

- shear strength by STN EN 392

Fig. 5 Scheme of tested samples by STN EN 392

- delamination by STN EN 391 4. RESULTS On the base of realised laboratory experiment and ob-tained results was proved, that the most suitable adhe-sive is polyurethane JOWAPUR 686.60. Reached shear strength were significantly better in comparison with RF and MEF - resins. According to shear strength values obtained in labora-tory we recommend for reinforcing of wooden build-ing structures PUR adhesive for industrial trials.

Figure 6: Fracture of the lower lamellae - non reinforced beam

Figure 7: Break of the reinforced beam inadmissible knot in the tension zone

17

Figure 8: Break of the reinforced beam inadmissible knot and fibre deviation

Figure 9: Destruction of the reinforced beam plucked carbon lamellae

Figure 10: Detail of the fracture of the finger-joint bottom plan

Figure 11: Detail of the fracture of the finger-joint different qualities of finger-joints gluing

From the presented figures it is apparent that quality of the spruce wood, the presence of the knots and fi-bre deviation (Fig. 7, 8) can remarkably affect strength and deformation also at the reinforced glulam beams and thus also reinforcement efficiency. Non re-inforced glulam beams were different in that the rein-forced beams have kept solid after lamellas destruc-tion, and the total destruction occurred at extremely high values of deflection. The effect of the quality of finger-joints gluing (Fig. 10, 11), their mutual dis-tance in lamellae and arrangement at cross-section were considerably shown technological factors. Ob-taining the suitable quality of the wood carbon lamel-lae bonding at using the PUR adhesive was effected mostly by thorough application of detergent on the carbon lamellas, the evenness of glue spread and keeping its opened time. 5. SUMMARY Carbon fibre-based lamellae offer new opportunities for timber structure designing. This work should con-tribute to a better understanding of the wood behav-iour in load bearing structures reinforced with carbon lamellae as well as to a better understanding of the in-fluence of the chosen physical and mechanical proper-ties of wood on the total behaviour of wooden ele-ments reinforced with carbon lamellae. REFERENCES 1. STEIGER, R., Fibre reinforced plastics (FRP) in timber constructions - investigations and develop-ments. Proceedings of the EUROWOOD Workshop 2002 on Engineered Wood Products - Innovation and Exploitation, VTT Helsinki, Finland, 2002 2.TEFKO, J., GRNIAK, M.: Vystuovanie dre-vench prvkov uhlkovmi lamelami.In: Uhlkov vlkna v drevench stavebnch kontrukcich, TU Zvolen, 2004. 3. Sika Slovakia s.r.o.: http://www.sika.sk This work was supported by Slovak Research and Development Agency on the basis of contract APVV-99-015805

18

- , e-mail: blagoevg@abv.bg

, - . , , 0.1%. - , - , - . , , 0.5%. - - , - . : , -, , - , , - - . - -, -, - (Lewis 1985, 1988, Todoroki 1990). - , - -.

- . - , - - ( 1986, 1995). , , , . , (1996), (2004), . -, , . . , . - .. . - - - - , - . , - . -

19

. - - . - , - , -. - - dsed=18.7025.65 cm, S=0.61251.8375 cm/m - L=4 m, . - =3.2 mm a . a , - , - . b , - , - . - - . - , .. . , , - , . - . , -, - - , - . - - . - - - , -

. - , - , - . , - - -. , , , . .1 , . - qb - Vri. , , . - - . - 0.01% 1 0.09% 3. , , - . 2 - - , . .1 , 1 - - 2 3. - 1 2 3 - ,

20

7 cm. , , - 1 cm - , 2 cm. , 1 , .. -, 2 3 , - , - . , - . .2 1, , 3 2. - - 1 - , , , . 42 mm - 3 , - 0.32% 1. 2 0.41% 1. .3 2 3, 1.

2 52.5 mm 47.0 mm - - 0.50%. , - 3 42.0 47.0 mm 0.31%. , - , - , 0.50%. - . 1. , . 2. - 0.1% , . 3. , - 0.5% , - -, - - .

21

1:

1

, 2

3

:

a [m

m]

b [m

m]

L [m

]

-

4 3

2 1

1 2

3

-

[m3 ]

.

R [%

]

1 d s

ed a

v = 2

2.75

cm

S

= 0.

6125

cm

/m

L =

4.0

m

p =

3.2

mm

a:

L =

4, b

4: L

= 3,

b3:

L =

2, b

2: L

= 1,

b1:

15.5

*

96

.72

65.6

3

2

1.0

100.

0011

5.14

157.

1214

3.23

2

6.0

166.

0017

7.77

201.

7719

3.52

4

7.0

206.

04

217.

17

233.

03

227.

62

4

7.0

206.

0421

6.44

226.

2322

6.48

2

6.0

163.

0017

5.49

180.

8619

0.05

2

1.0

100.

0010

8.95

104.

5613

5.00

V

ri =

0.18

3378

m3

q b =

0.1

210

m3

R =

65.

98 %

2 d s

ed a

v = 2

5.65

cm

S

= 1.

0125

cm

/m

L =

4.0

m

p =

3.2

mm

a:

L =

4, b

4: L

= 3,

b3:

L =

2, b

2: L

= 1,

b1:

21

.0*

96.0

214

5.14

82.6

2

26

.0*

170.

2419

6.05

174.

83

4

7.0

147.

7822

0.13

235.

7023

2.29

5

2.5

234.

32

265.

99

274.

15

284.

15

4

7.0

239.

2824

3.35

249.

3927

6.09

2

6.0

204.

7216

8.44

175.

1223

1.86

2

1.0

154.

30 16

5.14

V

ri =

0.25

0047

m3

q b =

0.1

6085

m3

R =

64.

33 %

3 d s

ed a

v = 1

8.70

cm

S

= 1.

8375

cm

/m

L =

4.0

m

p =

3.2

mm

a:

L =

4, b

4: L

= 3,

b3:

L =

2, b

2: L

= 1,

b1:

15

.5*

67.8

410

3.84

21

.0*

109.

4813

2.70

162.

70

2

1.0

123.

0616

2.10

175.

7320

6.10

4

2.0

160.

32

190.

37

200.

33

231.

60

4

2.0

157.

7719

2.97

193.

1522

8.48

2

1.0

114.

8016

9.36

155.

0819

7.50

2

1.0*

128.

1570

.93

141.

70

V

ri =

0.16

0445

m3

q b =

0.0

890

m3

R =

55.

47 %

22

2:

1

42.

0

52.5

mm

,

3

2

:

[mm

]

b [m

m]

L [m

]

4 3

2 1

1 2

3

-

-

[m3 ]

. -

R

[%]

a:

21.0

* 2

1.0

26

.0

42.0

42

.0

26.0

26.

0L

= 4,

b4:

59

.19

87.4

610

5.23

105.

2587

.34

50.0

4b 4:

59

.19

87.4

610

5.23

105.

2587

.34

50.0

4L

= 3,

b3:

44.0

365

.78

92.8

511

0.34

110.

0591

.90

54.2

9b 3:

43.1

766

.33

93.6

311

1.26

110.

9892

.68

54.7

4L

= 2,

b2:

50.8

090

.63

112.

2412

7.37

124.

4810

2.80

56.3

3b 2:

43.5

877

.75

96.2

910

9.27

106.

7988

.19

48.3

3L

= 1,

b1:

31.2

478

.78

101.

3711

6.80

116.

3499

.89

68.1

3b 1:

30.6

977

.39

99.5

811

4.74

114.

2998

.13

66.9

3a/

b/L:

20/6

0/2.

5 20

/110

/4

2x20

/20/

2 25

/170

/4

40/2

00/4

40

/200

/4

25/1

70/4

25

/90/

4

Vri

= 0.

1833

78 m

3

q b =

0.1

204

m3

R =

65.

66 %

a:

15.5

* 2

1.0

21

.0

52.5

52

.5 2

1.0

21.

0L

= 4,

b4:

48

.96

82.5

310

0.22

100.

2282

.53

48.9

6b 4:

48

.96

82.5

310

0.22

100.

2282

.53

48.9

6L

= 3,

b3:

56

.39

88.0

510

5.37

104.

9186

.89

53.2

2b 3:

56

.87

88.7

910

6.25

105.

7987

.62

53.6

7L

= 2,

b2:

50.8

083

.93

108.

2212

3.00

118.

3696

.76

54.9

5b 2:

46.8

572

.00

92.8

410

5.52

101.

5483

.01

47.1

4L

= 1,

b1:

31.2

471

.55

97.2

311

2.37

111.

6395

.44

67.3

1b 1:

30.6

970

.29

95.5

111

0.38

109.

6693

.76

66.1

2

1

d sed

av =

22.

75 c

m

S =

0.61

25 c

m/m

L

= 4.

0 m

p

= 3.

2 m

m

a/b/

L:15

/60/

2.5

20/9

0/4.

0 2x

20/2

0/2.

5 20

/160

/4.0

50

/190

/4.0

50

/190

/4.0

20

/160

/4.0

20

/90/

4.0

Vri

= 0.

1833

78 m

3

q b =

0.1

2025

m3

R =

65.

57 %

23

3:

2

3

47 m

m,

1

:

[mm

]

b [m

m]

L [m

]

4 3

2

1

1

2

3

-

-

[m3 ]

. -

R

[%]

a:

21.0

* 2

6.0*

47

.0

47.

0

47.

0

26.

021

.0*

L =

4, b

4:

81

.39

119.

6511

9.64

102.

3677

.15

b 4:

81.3

911

9.65

119.

6410

2.36

77.1

5L

= 3,

b3:

57.7

788

.72

110.

9013

1.32

118.

8282

.24

b 3:

60.5

592

.98

116.

2313

7.64

124.

5386

.20

L

= 2,

b2:

96.9

812

5.01

147.

3216

8.80

152.

1510

6.84

b 2:

61.9

879

.89

94.1

510

7.87

97.2

368

.28

L

= 1,

b1:

63.4

710

6.53

136.

0116

2.75

156.

3013

1.26

93.4

9b 1:

48.6

481

.65

104.

2412

4.73

119.

7910

0.60

71.6

5a/

b/L:

20/1

10/3

.5

25/1

60/3

.75

2x25

/45/

1.0

45/3

5/2.

0 45

/35/

2.0

25/2

5/1

20/1

20/0

.5

25

/45/

3.0

45/2

20/4

.0

45/5

0/4

25/1

40/4

20

/90/

1.5

45

/150

/4.0

45/1

50/4

25

/20/

2 2x

20/3

0/1

2

d sed

av =

25.

65 c

m

S =

1.01

25 c

m/m

L

= 4.

0 m

p

= 3.

2 m

m

20

/45/

1.0

25/2

0/1.

5

V

ri=0.

2500

47m

3

q b =

0.1

596

m3

R =

63.

83 %

a:

21

.0*

26

.0

47.0

47

.0

21.0

21.0

*L

= 4,

b4:

50.7

080

.66

80.6

658

.09

b 4:

50.7

080

.66

80.6

658

.09

L

= 3,

b3:

32

.08

66.8

285

.90

87.4

375

.19

53.5

6b 3:

37

.32

77.7

399

.93

101.

7187

.47

62.3

1L

= 2,

b2:

49

.18

75.6

092

.26

87.9

667

.43

9.19

b 2:

55

.48

85.2

810

4.08

99.2

376

.07

10.3

7L

= 1,

b1:

72

.37

101.

7412

1.19

119.

0810

0.49

66.2

4b 1:

63

.44

89.1

910

6.24

104.

4088

.10

58.0

7a/

b/L:

20

/100

/1.0

25

/100

/4.0

45

/160

/4.0

45

/160

/4

20/1

10/4

20

/110

/1.5

20

/20/

1.0

20/2

0/2.

0 45

/35/

1.0

45/3

5/1

2x20

/30/

1

3

d sed

av =

18.

70 c

m

S =

1.82

5 cm

/m

L =

4.0

m

p =

3.2

mm

25

/25/

2.0

V

ri=0.

1604

45m

3

q b =

0.0

885

m3

R =

55.

16 %

24

. 1960.

. -., .

. 2004. . .. , .

. 1989. - . ., .

. 1986. . ., .

., . 1988. - -. ., .

. 1996. - . -, 5, . 5-7.

. 1995. - - . .

Lewis D. 1985. Sawmill Simulation and the Best Opening Face Systwm. A users Guide US Department of Agriculture, Forest Service, FPL, General Technical Report FPL-48.

Todoroki C. 1990. Autosaw system for sawing simulation. New Zealand Journal of Forestry Science, 3, p. 332-348.

FACTOR EFFECTS IN THE APPLICATION OF ADEQUATE MODELS

FOR LOG SAWING

Georgi Blagoev University of Forestry - Sofia,

e-mail: blagoevg@abv.bg

SUMMARY Besides for calculations and analyses, the application of adequate models could be also in the technological processes of group processing of logs with sawing patterns considering equal thicknesses of lumber. The results showed that at constant levels of the factors the deviations of yield are about 0.1 %. In the cases when the lumber thicknesses in the inner zone of logs correspond to the adequate models, and the outer zone consists of thin boards with equal thicknesses, then specific models are applied, called models with equal board thickness. When unified sawing models are applied to broader diameter range logs, then the deviations in the quantitative yield are 0.5 %. These results confirm the opportunity for application both the adequate sawing models and regression analysis for mathematical processing of data. Key words: adequate models, factorial dependence, quantitative yield.

25

-

-

- - (P. Sylvestris L.). 202030mm. - ( ) ( - 2.5 86%) - , - . : , , , , -, - , -, , , - -. , , -, , - . - , - - . - - (Pinus silvestris L.). 1. . (Pinus silvestris L.) - 202030mm, 100 mm. 450 mm, 182-4 . -. -

- - Wackep ()-Silicon 290-L Siloxan H. - -(). - , . , . DIN-4 13s, 12s. Silicon 290-L 970 kg/m3, Siloxan H 900 kg/m3. - 0,08 30-60 min, - 30-60 min - . 6-24 h 80-120. 10 20 , . - , 30 ( ) , - 25% 86% ( Cl2 Cl). , 30- . - - - . - :

,%100.po

om

mm =

m mo - . -

,%100kp.k

kW

WWe

=

W , W .

26

, - .

- - . - - , - . - - . - .

.1 Silicon 290 L Siloxsan H = 2.5 %: 1,2,3, - Silicon 290 L,

4 , 5,6,7 - Siloxsan H.

.1 2 - Silikon 250L Siloxan H 2,5 86% -. .3. - . - . - ( = 86%) 15- - : 18%, - 9,7%, 8,3% 5,9% 16,7%, 29,9%

39,2%. - (.3).

.2 Silicon 290 L Siloxsan H = 86 %: 1,2,3, - Silicon 290 L,

4 , 5,6,7 - Siloxsan H.

- 15 : 111% (-), 65% ( 16,7%), 61% ( 29,9%) 39,1% ( 39,2%). , - Siloxan H e, Silicon 290L. - -- . - , .. - . 15 - :

- 86%; 17,1%, 7,4% ( 14,0), 7,2% ( 35,3%) 5,9% ( 37,4%).

- : 111%, 68,1% ( 14,2%), 68,8% ( 21,1%) 58,8% ( 37,4%). , Silicon 290 L - , Siloxan H. - . - - 5

27

.3 Silicon 290 L Siloxsan H; 1,2,3, - Silicon 290 L, 4

, 5,6,7 - Siloxsan H. . , .. - . Silikon 290L 0,8 3,30% 0,8 3,0 . - Siloxan H 1,5 4,0% ( ) 0,67 4,96%. , - . - 80% - , - -, .. , - -. - , , - . - - -, . 1.

- - .

2. - -,

. - .

3. Silicon 290 L Siloxan H - - , .. .

, . - -

. - , , 1988.

, .. . - -, ., , 1986.

Brebner, K., M. Schneider. Wood-polymer combi-nation: Bonding of alkoxysilane coupling agents to wood. Wood science technology, 3, 1985.

Schneider, M., K. Brebner. Wood-polymer combi-nation: The chemical modification of wood by alkoxysilane coupling agents. Wood science and technology, 3, 1985

WATER AND WATER-VAPOUR SORPTION OF SCOTS PINE WOOD IMPREGNATED

WITH SILICEOUS SUBSTANCES

Christofor Videlov University of Forestry - Sofia

SUMMARY The paper presents results of a study of the effect of two industrial products containing silicon on the water and water-vapour sorption of Scots pine (Pinus sylvestris L.) wood. The impregnation was done on samples 20x20x30 mm. The effect of the quantity of impregnated substance on water sorption (after soaking in water) was tested, as well as on water-vapour sorption (in an excicator at relative air humidity 2,5 and 86 %). Significant decrease in both characters studied was found, depending on the type and quantity of the impregnated substance. Key words: Scots pine timber, impregnation, silicons, water sorption, water-vapour sorption, dimensional stabilization of wood, chemical modification of wood

28

,

1, , , 1e-mail: bluskova@hotamail.com

, , , - . - - . , - . , . , - . - . , , , - , , . - .

. 1.

- . - - . . . . , - . - - , , - , -. -, - , - , . - , - , . - . - . , - , - , . (.2.).

.2.

: CV -, ; CM ; CH ; DZ , ; DH MZ

29

, ; MH , HV ; PL ; S - ( ., 1993). , -, , . - , , .. - -. , . - - , , .. , , - , - . - - . - -, - -

. - - , e . (Stajduhar, F., 1970). - - - . : - - 2,7 mm , 1,8 mm. -718 kg/ m3, --663kg/m3 8,3% . - -58,2 N/mm2, - 54,3 N/mm2 7,2% , -130,0 N/mm2, -109,2 N/mm2 19% . -65,0 N/mm2, 57,2 N/mm2 13,6% . 11,8%. - , - .

1.

, %

F.Stajduhar . 718 kg/m3 663 kg/m3 8,3 4,3

58,2 N/mm2 54,3 N/mm2 7,2 8,3

130,0 N/mm2 109,2 N/mm2 19 2,9

: - / 65,0 N/mm

2

57,2 N/mm2 13.6 9,5 ; 9,3 -

( .) :

1. 4,3% - .

2. - 12,2%

3. - ; - 8,3%, 9,5% 9,3%.

4. 3,4%, 2,9%, 20%. , -

, .

5. , . - -. ;

10,3%.

43,1%

18,2%

30

53,3%. -

4,8% 1,2%

- .

(. 1), , .

- (Wobst H., 1967). - -: 1. . - - . - - (. 2).

. 2 .

1 2 3 1-3

. . . . 39 47 32 36 19 29 90 112

X g/cm 0,623 0,652 0,651 0,638 0,687 0,690 0,647 0,657 qx 0,006 0,007 0,011 0,009 0,008 0,008 0,007 0,006 s% 2,9 3,5 4,6 4,2 2,4 2,9 5,1 4,7

- ; X g/cm ; qx - s=95%; s% - . 2. - , . -. 3. , - . - . - - . .. . , - . - - -, , . , - - - . - , - . . , -

, . . 4. , 19 . , - . , 34,6% . , - 14,3%. - 23,8%. - , , -. - . 5. , , 18 . . , 24,65% - , - 0,28%. 17,9%. - , - , .

31

74,16%. - - . 6. , 19 . , . , 34,6% - , - 14,3%. 23,8%. , , . . - 27,07%. - - . 7. - , - 3, - - 2(18%).

, . -, 260 mm. , - . - -. - - -. , - - 400 mm. - - . , . - . . , 1994. , ., -, 1993. , ., , 1972

, . , . , ., , 1994. Stajduhar, F. Koriscenje nepravi srzi bukovine.-Drvna industrija Krahl-Urban, 1967 ber dis Drehwchs bei Buchen.-XIV IUFRO-Kongress, Kabiecova, M., 1984 Zahnednutie bukovno dreva po stnke.-Drevrsky Vskum, 29, Sachsse, H., R. Ferchand, 1988 Abnorme Kerne bee Rotbuche.-Holz als Roh-und Werkstoff, 46, Wobst, H., 1967 Auswirkungen der Rotverkernung von Buchenstammholz auf einige kennzeichende physikalische und mechanisch-tehnologische Eigenschaften.-XIV IUFRO Kongress

STUDY ON THE ABNORMAL HEARTWOOD OF ROUND WOOD

Genka Bluskova1, Nikolay Bardarov, Marina

Naydenova University of Forestry Sofia, 1e-mail:

bluskova@hotamail.com

SUMMARY It is well known that round wood used in the woodworking industry has increasingly become scarce and has exhibited a number of defects. It is of interest for the woodworking industry to understand the condition of the raw material and to be supplied with round wood without defects. Abnormal heartwood is the unusual coloring of the trunk center which is caused by different factors. The coloring of this part may be in various shades, intensity and colour uniformity without decreasing the wood hardness when the heartwood has not decayed. This defect is observed in standing timber of tree species without normal heartwood such as beech. This abnormal heartwood can be used but it is necessary to find out what its percentage and condition is. The density of abnormal heartwood is not so different from the one of the peripheral layers. Similar to the density, no significant difference has been found in the radial and tangential shrinkage of abnormal heartwood and sapwood. The same is true about compression strength along the fibres, volume shrinkage and bending strength.

32

WOOD STRUCTURE OF CAUCASIAN WHORTLEBERRY (VACCINIUM ARCTOSTAPHYLOS L.)

1Genka Bluskova, Aleksander Tashev, Nikolay Bardarov University of Forestry, 1e-mail: bluskova@hotamail.com

SUMMARY In Bulgaria, Vaccinium arctostaphylos L. is included in the Red Data Book as endangered species, and it is shown that it is a Tertiary relict. The species is in-cluded in List of Rare, Threatened and Endemic Plants in Europe under the category rare (Lucas 1977, 1983) , and in APPENDIX I (valid from 5 March 1998) STRICTLY PROTECTED FLORA SPECIES of the Convention on the conservation of European wildlife and natural habitats. Since 1961 V. arctostaphylos L. has been included in the list of plant species in Bulgaria, protected by the law. In Bulgaria, Vaccinium arctostaphylos L. is a decidu-ous shrub with smooth bark and is up to 3 m high (Antchev 1982). In other parts of the areal, it can be a deciduous shrub or tree with a height of up to 4 m, whose branches have a round cross-section. Data on distribution of the species are scarce. In lit-erature sources in Bulgaria, it is said that it is found rarely only in Strandja Mountain as individual speci-mens or small groups. It is found in shady and damp beech forests (Stoyanov & Stefanov 1925) and par-ticipates in forest communities of Fagus orientalis and Quercus polycarpa (Red Data Book of the PRB, V. I, 1984) at an altitude of 150 to 700 m (Antchev 1982), and according to the chorological card-index of the Forest Institute of the Bulgarian Academy of Sci-ence at 50 to 200 m altitude. Besides in Bulgaria, the species is found in Southeast Europe (Turkey), Southwest Asia, and Caucasus. In Caucasus, it occurs at different altitudes, starting from sea level, but most often it is distributed between 1000 and 2000 m in plant communities which are very various beech, fir-spruce, fir-beech, chestnut, oak, rhododendron shrubs. At the upper limit of the forest in birch, even in pine forests. In subalpine zone, the Caucasian whortleberry forms big groupings (Komarov 1952, Sokolov 1960). According to Goulisashvili 1967, Vaccinium arctostaphylos L. has tropic relict origin, which is proved by double and even triple flowering. Key words: Caucasian whortleberry, Vaccinium arc-tostaphylos L., wood structure MATERIALS AND METHODS

Wood specimens used for this investigation are taken form the biggest locality of Vaccinium arctostaphylos L. in Bulgaria (Valtchev & Tashev 1995). It is a spe-cies population developing at the lower part of a

southern slope at an altitude of 250 m. The territory occupied by Vaccinium arctostaphylos L. has the shape of an irregular hexagon with an area of 0.45 ha. The soil there is maroon forest, ?, sandy-clayey, slightly to medium stony, medium deep. At some places, there is a developed dead forest litter with a depth of up to 2 3 cm. The locality is situated in a mixed forest community of Fagus orientalis and Quercus polycarpa which form its first storey. The second storey of the commu-nity is built completely by the Caucasian whortle-berry. There, 563 shrubs have been found, with a height of 7 to 290 cm and a diameter of the stem at the base up to 3 cm. The crowns of the shrubs reach up to 3.5 3.7 m in diameter. The third storey of the community consists of Erica arborea which, like Fagus orientalis, is a Tertiary relic. The test wood is taken from shrubs with a height of about 2.00 2.20 m and a diameter at the base 2.5 3.0 cm. RESULTS AND DISCUSSIONS

Growth ring boundaries are distinct. Wood in narrow rings is diffuse-porous, and in wider rings semi-ring-porous. Vessels are solitary and their outline is angular. Perfo-ration is scalariform with 10 to 20 bars. Intervessel pits are scalariform. Tangential diameter of vessel lumina is smaller than 50 m. Tracheids are with common pits in both radial and tangential walls. REFERENCES

Antchev, M. 1982. Rod Vaccinium L. (Genus Vaccinium L.) Flora na NRB (Flora of the Peoples Republic of Bulgaria), Vol. VIII, Bulgarian Academy of Sciences , Sofia. 294-297. Greguss, P. 1959. Holzanatomie der europischen Laub-hlzer und Strucher. Akadmiai Klad, Budapest. Gulisashvili, V. Z. 1967. Proizhozhdenie drevesnoi rastitelnosti subtropicheskogo i umerennogo klima-tov i razvitie ee nasledstvennyh osobennostei (Origin of forest vegetation of subtropical and moderate cli-mates and development of its hereditary features). Medfanebo, Tbilisy. 218. Komarov, V. L. (Ed.). 1952. Flora SSSR (Flora of the USSR), Vol. XVIII. Rod Vaccinium L. (Genus Vaccinium L.). 94-102.

33

Table 1. Some features of Vaccinium myrtillus L. and Vaccinium oxycoccos L. wood

Growth rings Boundaries indistinct. Boundaries indistinct. Vessels Wood diffuse-porous. Early and late wood not distinguishable.

Vessels almost always solitary. Vessel outline circular, elliptic or angular. Shape and size of vessel members are similar. Thin-walled. Simple or scalariform perforation plates. Sscalariform perforation plates are more usual. Sscalariform perforation plates vary strongly in shape and size. Shorter or longer ellipses with distinct outlines. 2 to 10 bars in perforation plates. In some cases they are more indistinct and sometimes pass gradually into bordered pits on the radial wall.

Wood diffuse-porous. Simple or scalariform perforation plates. Scalariform perforation plates may form transition to bordered pits. Intervessel pits are dense.

Tracheids and fibres

Large number of thin-walled fibres and fibre-tracheids are observed.

Fibre-tracheids with narrow cell lumina

Axial parenchyma

Rare Rare

Geographical distribution

Europe, North Asia Middle and North Europe, North America

Lucas, G. 1983. List of rare, threatened and endemic plants in Europe. Strasbourg. Lucas, G. 1997. List of rare, threatened and endemic plants in Europe. Strasbourg. 286. Red Data Book of the Peoples Republic of Bulgaria. 1984. Vol. I. Rasteniya (Plants). Sokolov, S. Ya. (Ed.). 1960. Derevya i kustarniki SSSR (Trees and shrubs of the USSR). Vol. V. Rod

Vaccinium L. (Genus Vaccinium L.). 356-362. Stoyanov, N. & B. Stefanov. 1925. Flora na Bulgariya (Flora of Bulgaria). Sofia, Sofia University. 856. Valtchev, V. & A. Tashev. 1995. A new locality of Vaccinium arctostaphylos L. in Bulgaria. Simposium 125 years Bulgarian Academy of Sciences and 65 years Forest Research Institute. 22-23 September 1994 Sofia. 117-121.

Figures

34

(VACCINIUM ARCTOSTAPHYLOS L.)

1 , ,

- , 1e-mail: bluskova@hotamail.com

Vaccinium arctostaphylos L. , . , (Lucas 1977, 1983) .APPEN-DIX I ( 5 1998) - -. 1961 Vaccinium arctostaphylos L. , .Vaccinium arctosta-phylos L. - 3 m ( 1982). 4 m, . - Vaccinium arctostaphylos L. (, 1995) ,, 250 m. -, Vaccinium arctostaphylos L. - 0,45 ha. - . - , - .

- . , -. - . . - (.3) -. - - - . 10 20 . - - - . - 50 m. . . - (.5). -, . . . . - - . , - . 30 40 . . , , 4-5 . - . - . -. : , Vaccinium arctostaphylos L.,

35

, ,

- , e-mail: niki_bardarov@yahoo.com

, - , - - - -. . (.. 0), 15; 30; 45 60 . , , , . - .

- . 1.

- -, , - - (. 1). - . - - -.

. 1 . (), (), (), () ()

- -. - . (2W) (L), , (. 2). -, , -

.. - - . , , , . , .. .

. 2

. 3 (Bucur, V., 1995)

36

, - . - - , - .. (. 3). - - , . 2.

, - . - Laboval , 32, 100 400. 32 , - ( ). 100 . 400 (2W) (L) . - (.. 0), 15; 30; 45 60 - . - -, -. 10 - . - , . :

1) , - - [ 32]; 2) - - [400] 2W L.; 3) [100] 2W.+L.; 4) S., S.. S..; 5) 2Wcp/Lcp.

- . - (Denne, 1988). 3.

. , (. 4 7). , - (. 8). - . 0,7 - (. 4). -, -, (. 1,). - 0,15 0,40 ( 0,46) ( 1). - - -, 1,20.

0,00

0,200,40

0,600,80

1,001,20

1,40

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

15 30 0 45 60

0,000,200,400,600,801,001,20

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

. 4. .

- - ,

(. 5). , , 0,2 .

37

0,00

0,20

0,40

0,60

0,80

1,00

1,20

1,40

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

15 30 0 45 60

0,000,200,400,600,801,001,201,40

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

. 5. .

. - - -, - (. 1,). 0,5 1,0 1,2 ( 1,01) ( 1).

- - . - - ( -) -. , - (. 1,). - 0,63 0,83 ( 0,78) (. 6).

0,500,550,600,650,700,750,800,850,900,95

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

15 30 0 45 60

0,50

0,60

0,70

0,80

0,90

1,00

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

. 6. .

- , - - . , - --

(. 7). - (. 1,). - 0,5 1,5 ( 1,06) ( 1), .

0,00

0,50

1,00

1,50

2,00

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

15 30 0 45 60

0,00

0,50

1,00

1,50

2,00

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

. 7. .

38

- , - (. 1,). - 0,5 0,9 ( 0,68) (

1), - . - , - -.

0,20

0,40

0,60

0,80

1,00

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

15 30 0 45 60

0,20

0,40

0,60

0,80

1,00

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

. 8. .

- -

.

1.

. 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0

0,15 0,15 0,20 0,25 0,25 0,30 0,37 0,91 1,13 0,89 0,47 1,09 1,03 1,12 1,07 1,13 1,11 1,12 0,99 1,00 0,63 0,79 0,81 0,79 0,81 0,81 0,80 0,83 0,79 0,79 0,58 0,64 0,86 0,91 1,02 1,23 1,27 1,29 1,35 1,43 0,67 0,69 0,66 0,55 0,82 0,55 0,72 0,70 0,61 0,78 - . - -

. - -.

1.

. 0 15 30 45 60

0,46 0,46 0,48 0,45 0,45 1,06 0,99 0,98 1,02 1,01 0,81 0,79 0,78 0,78 0,77 0,93 1,19 1,14 1,15 0,90 0,74 0,66 0,67 0,65 0,67 5.

-

-, .

, - .

- .

39

6.

1. , .., . 2004. - . . . -, (11-25; 71-74).

2. Wagenfuhr, R., Chr. Scheiber, 1974. Holzatlas. VEB Fachbuchverlag, Leipzig, (627-629).

3. Ifju G. 1983. Quantitative wood anatomy certain geometrical - statistical relationship. Wood and fi-ber science. 15, 4, (326337).

4. Kollmann, Fr.F.P., W.A. Cote Jr., 1968. Princi-ples of Wood Science and Technology. I Solid Wood. Springer-Verlag Berlin Heidelberg New York, (274-291).

5. Saint-Andre L. J.-M. Leban. 2000. An elliptical model for tree ring shape in transverse section. Methodology and case study on Norway Spruce. Holz Roh- und Werkstoff, 58, 5, (368374).

6. Wagenfuhr, R., 1988. Anatomie des Holzes: unter besonderer Beruckichtigung der Holtztechnik. VEB Fachbuchverlag, Leipzig, (185-213).

STUDY ON THE WOOD STENOSIS OF SCOT PINE, OAK, WALNUT, BEECH AND DABEMA

Nikolay Bardarov

University of Forestry - Sofia, e-mail: niki_bardarov@yahoo.com

SUMMARY The tree species whose wood is of economic importance are divided into 5 groups and the differences between the wood structure of the separate groups are much greater than the structure differences within each group. The basic anatomical indicator of wood structure is stenosity. It is a result from successive. Radial measurements of the cells (at 0o) and at angles of 15o, 30o, 45o and 60o bet. The radial axis and the axis of measurement. Representatives of each of the following groups heve been studied Scot pine, Oak, Walnut, Beech and Dabema. The test results can be used as an indicator for defining the species. A difference has been observed in venations of stenosis within the separate groups.

40

- , e-mail: niki_bardarov@yahoo.com

. . , , . , .. - . - . ,

, 15, 20-40 45%. , - 8,0, 10,0-16,0 18,0% . - . 1.

. (. 1). - (Pinus silvestris L.), . (Picea abies Karst.), . (Abies alba Mill.) (Taxus baccata L.).

. 1 Pinus silvestris L. (), Picea abies Karst. (), Abies alba Mill. (), Taxus baccata L. ().

- , .

- - ( 1).

1. (Fengel et al., 1989)

, [%] -, [m]

, 12 [kg/m3]

, [%]

Pinus silvestris L. 3100 30,0 93 1,4-5,8 5,5 490 67.3 Picea abies Karst. 2900 30,0 95 1,4-5,8 4,7 430 71.3 Abies alba Mill. 4300 50,0 90 9,6 410 73.0 Taxus baccata L. 1950 20,0 86 14,0 670 58,3 - ( ) . - , . -

- , . - - , ..

41

2.

, - . - Laboval , - 32, 100 400. , - . - - . :

1) , - [ 32 100]; 2) - [400];

: 3) 2W.+L.; 4) 2Wcp/Lcp; 5) , - S., S.. S..; 7) , %.

- . , , : 15, 20-40 45%. , 2Wr=Lr (, ), 4Wr=Lr. (). : 8,0; 10,0-16,0 18,0% . - .

- , - , (2Wr+Lr) (2Wcp/Lcp). - - , . (2W./L.) . - . 3. , (52,7%) , , . - (12,0%) - . (20,2%) . - (12,8%). . , .. . - . , - , -. - - -.

2.

/ .. 12,0 20,2 12,8 52,7 -

- ,% - 22,3 22,2 23,3 39,7

- 29,2 32,8 31,5 25,6 15,1 13,5 12,9 16,3 - 10,04 8,78 8,90 15,61

-

22,3 23,5 23,3 21,0 - 5,8 6,0 4,5 5,1 9,0 8,9 9,2 8,0 - 9,1 8,4 9,9 7,7

-

6,8 6,9 6,6 6,3 - 34,0 37,7 35,0 28,1 25,7 28,1 26,5 23,6 - 22,1 25,7 24,8 23,3

P , (2W.+L.)

29,9 33,1 31,3 25,9

42

(22-23%), ( 40%). - - - . . . - (- 2). - 23,5 23,3 m, - 21,0 m. , , , - . - . - - , .

, - . . (2W.+L.) - - ( 2). - - , - -. . (2W./L.) . , . , . -, , -.

3. .

- 0,21 0,20 0,15 0,23 0,56 0,48 0,56 0,53 - 0,77 0,50 0,71 0,51 2W./L.

0,39 0,31 0,36 0,36 - 282,9 324,5 233,2 205,6 299,1 329,1 316,2 246,9 - 252,3 286,4 307,9 237,3

- S..

270,4 309,4 262,6 220,6 - 637,9 803,5 744,9 420,7 225,9 297,7 245,1 197,8 - 148,6 242,9 186,1 202,4

- S..

467,7 585,6 538,8 319,4 - 68,9 70,6 75,5 66,8 42,0 46,5 42,8 43,3 - 34,3 45,2 36,6 44,5 ,%

57,5 60,8 61,1 56,4 . - - -, - . - - (S..=S..) ( 2 ). 0,7 -

, 0,7, - 0,7 - 0,6. , . (, %) - -, - . - - .

43

4. . 2

0,0

100,0200,0

300,0400,0

500,0

600,0700,0

800,0

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

,

0,00

0,20

0,40

0,60

0,80

1,00

1,20

S2Wcp SLcp (2Wr+2Wt)/(Lr+Lt)

0,0010,0020,0030,0040,0050,0060,0070,0080,0090,00

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

, mm

.,

%

(L+2W)cp , %

. 2, Pinus silvestris L.

0,0

200,0

400,0

600,0

800,0

1000,0

1200,0

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

,

0,00

0,10

0,20

0,30

0,40

0,50

0,60

S2Wcp SLcp (2Wr+2Wt)/(Lr+Lt)

0,0010,0020,0030,0040,0050,0060,0070,0080,0090,00

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

, mm

.,

%

(L+2W)cp , %

. 2, Picea abies Karst.

0,0

200,0

400,0

600,0

800,0

1000,0

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

,

0,00

0,20

0,40

0,60

0,80

1,00

S2Wcp SLcp (2Wr+2Wt)/(Lr+Lt)

0,0010,0020,0030,0040,0050,0060,0070,0080,0090,00

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

, mm

.,

%

(L+2W)cp , %

. 2, Abies alba Mill.

0,050,0

100,0150,0200,0250,0300,0350,0400,0450,0500,0

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

,

0,00

0,10

0,20

0,30

0,40

0,50

0,60

0,70

S2Wcp SLcp (2Wr+2Wt)/(Lr+Lt)

0,0

10,0

20,0

30,0

40,0

50,0

60,0

70,0

80,0

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

, mm

.,

%

(L+2W)cp , %

. 2, Taxus baccata L. ().

44

5.

- , 1-2 mm - , .

.

, - , - - .

- - .

- - . 6.

1. , ., . , . .

1980. - . - . , 20, (1115).

2. Denne, M.P. 1988. Definition of latewood according to Mork. IAWA Bulletin n.s.10, 1,(5962).

3. Wagenfuhr, R., Chr. Scheiber, 1974. Holzatlas. VEB Fachbuchverlag, Leipzig, (627-629).

4. Kollmann, Fr.F.P., W.A. Cote Jr., 1968. Princi-ples of Wood Science and Technology. I Solid Wood. Springer-Verlag Berlin Heidelberg New York, (274-291).

5. Wagenfuhr, R., 1988. Anatomie des Holzes: unter besonderer Beruckichtigung der Holtztechnik. VEB Fachbuchverlag, Leipzig, (185-213).

DETERMINATION OF SOME ANATOMICAL INDICES

OF CONIFEROUS TREE SPECIES

Nikolay Bardarov University of Forestry - Sofia,

e-mail: niki_bardarov@yahoo.com

SUMMARY The coniferous tree species are divided in five groups according to the presence and structure of the resin canals. The structure of the annual ring is also an im-portant diagnostic feature. In the present research wood from Scots Pine, Norway Spruce and Yew has been studied. The differences in the structure of the annual ring width of the latewood zone, transition from early to latewood, etc. has been studied in the present re-search. Except being an important diagnostic feature in determining the tree species it also affects their utilization. The border between earlywood and latewood has been determined by the equation between the surface of the cell walls and cell cavities. This index has been di-vided in the degrees 15, 20-40 and more than 45%. The size of the transition zone has been determined using the Morks rule and values 8,0, 10,0-16,0 and more than 18,0% of the earlywood. The position of the zone has also been determined.

45

E , e-mail: ekaterina.trichkova@mail.bg

- , - . , . -. - 1030%. - , -, - ; . : -, -, - . - - - - . - , - . , e - . -, - . ( - 2530 %) , - 2225 %) . , - , - . - - - . - -

-. -, - . - , -. , - , -, , - . , - - - . - //, - , - //, - - /n/. , 20 . - - - /1/. - . . - -

46

. 0,01 N/mm2.min, 45 - 1 N/mm2. - 35 . - . 1 N/mm2 . . - , - . - , . - , - . , 1. - - - , . - - . - - (, -, -) . - - - , - , -. . - - - . , - - . (2). - - - . - .-

, . .0 .3 ( 1) . ( 2). - 2 .0 3, - -. 3 1 -. (3). - :

1

.

=H (1)

2

.

=E (2)

( )EHEn

=.

. 23 (3)

: ; - (min); 1 - 1; 2 - 3; 3 - 3,

1. . - - . - - 0,001mm, - .

ll

= , l -

l. , 5 - /Fagus Silvatika L/ - 542560 kg/m3, - 10,1% 29,8% 20. -, . - - .

47

- . , - 14,8 15,3% , - , - 20 min - 0,001. - . - 0,0021, - -. 10 min . 130- min 0,0044. - 0,002. - 20 min. 0,0067 ..(. 1) - .3. 2. - - . , 3 , 4 . 10 30 % -

4 . - - - - . - -. 20% - 4,5 N/mm2 4,41 N/mm2. , . 3 - 10%, - -. 36,6% - . . - 20 % 20 4. - - . 30 % (), 70% (), 37% , 60% -. - - - , .

1: 15% 200

[N/mm2] 1,0

2,0 3,0

V 4,0

V 5,0

+ 0 +100 10 +100 20+100 30+100 40+100 [] [] : 20 40 50 60 70

, 0,0022 0,0044 0,0067 0,093 0,0121 , . 0,0012 0,0024 0,0042 0,0064 0,0090 , . 0,0010 0,0020 0,0025 0,0029 0,0031

2:

[%] [N/mm2] [N/mm2] N [min]

[N/mm2]

10 503,0 1070,0 174 8,2 12 500,0 955,0 163 7,5 15 381,0 852,0 135 6,5 20 320,0 747,0 109 4,6 25 211,0 610,0 75,6 3,4 30 159,0 485,0 43 1,8

48

3: 10%

-

[N/mm2]

[N/mm2]

n [min]

[N/mm2]

1070,0 503,0 174 8,2 930,0 545,0 167 5,2 13% 8 % 4% 36,6%

4: - 20%

-

[N/mm2]

[N/mm2] n

[min]

[N/mm2]

320,0 747,0 109 4,6 4150,0 1270,0 174 6,3

1. .. - ; , 1963/2.

2. .. - . - , 1971.

DEFORMATIONS AND RHEOLOGYCAL PROPERTIES OF WOOD

Ekaterina Trichkova Vetova

University of Forestry Sofia, e-mail: ekaterina.trichkova@mail.bg

SUMMARY

Wood is flexible plastic stuff that reveals complex rheological character in the conditions of pressure. During its drying, in it appear deformations and pressure which may be dangerous for its integrity. Their size depends on moisture content and temperature of wood. The report treats the influence moisture content in the range of 1030 %. In the research considered the sizes of wood deformations total, elastic and residual as well as the rheological coefficients- momentary module of flexibility, prolonged module of flexibility and relaxation time.

Keywords: deformations-total, elastic, residual, rheological coefficients- momentary module of flexibility, prolonged module of flexibility, relaxation time.

49

- , e-mail: igenov_03@abv.bg

. -, - - .

- -, - , , , . , .

.

. - ( ) .

-, , - - . - . , , - 20 , . , - - -. , , 16% , . , : , . - -

. : -, - . - . , - - . - . , . , - 45% . - - . - , - , - -. , - -, - - , - , , , , , - . - - . , . - . -

50

- , -- . - -, - , - . , -, - . 90%. . - , . - 50% . - , - 90% . - . - , , - -. - . - , - , - . - , - - , . - , . - - , , - , - /, , / - //, . . - .

- - . - - . - - , , - - 1200-1400 kg/m3. - - - . - -. , - - , - - . - . - , . - , . - - , - , , . - . - - /, , -/ . - - - , , . , , - -

51

- , . . - . - -. . -. , - . , - , . - , - , - -. ,