Автор: Assia Marinova
- STUDY ON STIFFNESS COEFFICIENTS UNDER BENDING TEST OF END CORNER DETACHABLE JOINTS OF STRUCTURAL ELEMENTS MADE OF PLYWOOD
In this study are given the results from investigation into stiffness of end corner detachable joints of structural elements made of beech veneer plywood. The stiffness coefficients under compression bending test have been determined. The highest stiffness is characteristic of joints with universal connector and screw for wood ø 6 х 90 and ø 6 х 80 mm while the lowest stiffness is typical of joints with Minifix with bolt, mounting in metal sleeve and direct mounting. The parameters of the screw joints have considerable impact on the stiffness characteristics of the joints.
It is recommended that the comparative data of bending strength be taken into consideration when selecting the type of joints in the construction of furniture made of plywood.
Ключови думи: furniture construction, plywood, joints, stiffness
- COMPARATIVE RESEARCH ON THE DESTRUCTIVE BENDING MOMENTS OF SOME CORNER JOINTS OF FRAME STRUCTURAL ELEMENTS MADE OF SOLID SPRUCE WOOD WITH A CROSS SECTION OF 50 X 30 MM PART III: END CORNER MORTISE AND TENON JOINTS
The results from the research on the destructive bending moments of the end corner mortise and tenon joints of structural elements made of solid spruce wood with a cross section of 50 x 30 mm are given whereas these joints are used mainly in the construction of sitting furniture, tables and beds.
It was established that the type of joints has significant influence on the destructive bending moment. This is defined by the type and size of joint elements and the area of the contact surfaces of the joints.
The following joints are destroyed at a considerably big bending moment:
- Haunched blind mortise and tenon joint;
- Blind twin mortise and tenon joint;
- Blind mortise and tenon joint
- Haunched through twin mortise and tenon joint;
- Haunched through mortise and tenon joint;
- Haunched blind twin mortise and tenon joint;
- Twin through mortise and tenon joint;
- Through mortise and tenon joint.
It is recommended that the research results are taken into consideration in strength design of furniture.
Ключови думи: corner joints, frame structural elements, destructive bending moments, solid spruce wood
- NORMS FOR DESTRUCTIVE BENDING MOMENTS OF T-SHAPE CORNER JOINTS OF FRAME STRUCTURAL ELEMENTS MADE OF SOLID SPRUCE WOOD WITH A CROSS-SECTION OF 50 Х 30 MM
In the presented research are established the normative values for the destructive bending moments of the most common used T-shape corner joints of frame structural elements made of solid spruce wood with a cross-section of 50 х 30 mm in arm compression bending load.
The established normative values can be used for the needs of the preventive quality control of furniture production as well as for the strength design of the sitting furniture, tables, and beds. For that purpose, it is recommended to draw up these normative values as a normative document which to use in the inner factory control of furniture quality.
Ключови думи: corner joints of frame structural elements, destructive bending moments, solid spruce wood, norms for destruc-tive bending moments of T-shape corner joints