Tensile tests on plywood, Plywood as a Construction Material, Uses of Plywood as a Building Material, IS : 1734 (Part 9) - 1983, Universal Testing Machine (UTM), Construction Materials Lab, Plywood as a Construction Material :- Plywood as a building material is very widely used due to its many useful properties. It is an economical, factory-produced sheet of wood with precise dimensions that does not warp or crack with changes in atmospheric moisture. Ply is an engineered wood product made from three or more 'plies' or thin sheets of wood. These are glued together to form a thicker, flat sheet.  Uses of Plywood as a Building Material :- Plywood has a huge range of uses within the construction industry. Some of its most common uses are: To make light partition or external walls To make formwork, or a mould for wet concrete To make furniture, especially cupboards, kitchen cabinets, and office tables As part of flooring systems To make light doors and shutters. The tensile strength when determined by the method described in IS 1734 (Part 9) shall comply with the following values: a) Tensile strength shall be not less than 42.0 N/mm2 in the direction parallel to grain direction of the face veneers. b) Tensile strength shall be not less than 25.0 N/mm2 in the direction of right angles to the grain direction of the face veneers. c) Sum of the tensile strength in both directions shall be not less than 84.5 N/mm2. Procedure :- Specimen should be placed under Universal Testing Machine (UTM) and the load shall be applied continuously throughout the test at a rate of traverse of the movable head of 1 mm/min. The specimen shall be held in wedge-type self-tightening and self-aligning grips. Note the load at which plywood specimen fails (kg). Calculate Maximum tensile stress (N/mm2) = (𝐹𝑎𝑖𝑙𝑢𝑟𝑒 𝐿𝑜𝑎𝑑)/(𝐴𝑟𝑒𝑎 𝑈𝑛𝑑𝑒𝑟 𝑇𝑒𝑛𝑠𝑖𝑜𝑛). Report the average of tensile stress parallel to face grain of three plywood specimens as Maximum Tensile stress parallel to face grain. Report the average of tensile stress perpendicular to face grain of three plywood specimens as Maximum Tensile stress perpendicular to face grain.

1. TESTS ON PLYWOOD
Mayur. U. Rahangdale
M.Tech (Construction Management – VJTI, Mumbai)
Construction Materials Laboratory
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2. DETERMINATION OF TENSILE STRENGTH OF
PLYWOOD
IS : 1734 (Part 9) - 1983
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3. THEORY
 Plywood as a Construction Material
• Plywood as a building material is very widely used due to its many useful properties. It is
an economical, factory-produced sheet of wood with precise dimensions that does not warp or
crack with changes in atmospheric moisture.
• Ply is an engineered wood product made from three or more 'plies' or thin sheets of wood. These
are glued together to form a thicker, flat sheet.
 Uses of Plywood as a Building Material
• Plywood has a huge range of uses within the construction industry. Some of its most common uses
are:
• To make light partition or external walls
• To make formwork, or a mould for wet concrete
• To make furniture, especially cupboards, kitchen cabinets, and office tables
• As part of flooring systems
• To make light doors and shutters
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4. The tensile strength when determined by the method described in IS 1734 (Part 9)
shall comply with the following values:
• a) Tensile strength shall be not less than 42.0 N/mm2 in the direction parallel to
grain direction of the face veneers.
• b) Tensile strength shall be not less than 25.0 N/mm2 in the direction of right
angles to the grain direction of the face veneers.
• c) Sum of the tensile strength in both directions shall be not less than 84.5 N/mm2.
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5. AIM
• To determine Tensile Strength of plywood parallel to face grain and
perpendicular to face grain.
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6. Equipment for Tensile Strength of plywood
• Universal Testing Machine (UTM) :
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7. 7
• Plywood Specimen:

8. Testing Procedure
• Measure the specimen area under tension (in mm2).
• Specimen should be placed under Universal Testing Machine (UTM) and the
load shall be applied continuously throughout the test at a rate of traverse of the
movable head of 1 mm/min. The specimen shall be held in wedge-type self-
tightening and self-aligning grips.
• Note the load at which plywood specimen fails (kg).
• Calculate Maximum tensile stress (N/mm2) =
𝐹𝑎𝑖𝑙𝑢𝑟𝑒 𝐿𝑜𝑎𝑑
𝐴𝑟𝑒𝑎 𝑈𝑛𝑑𝑒𝑟 𝑇𝑒𝑛𝑠𝑖𝑜𝑛
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9. 9
Tension Failure Mode (Parallel to grain)
Tension Failure Mode (Perpendicular to grain)

10. Reporting of results
• Report the average of tensile stress parallel to face grain of three
plywood specimens as Maximum Tensile stress parallel to face grain.
• Report the average of tensile stress perpendicular to face grain of three
plywood specimens as Maximum Tensile stress perpendicular to face
grain.
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