Shuttering Plywood Testing(IS 4990:2011)
Testing of plywood for concrete shuttering and formwork per IS 4990:2011 — BWP bond verification by 72-hour boil, glue shear strength, static bending and moisture content — before it faces wet concrete and repeated reuse cycles.
What is Shuttering Plywood Testing?
Shuttering plywood works in the harshest panel environment on any site — clamped, nailed, loaded with wet concrete, steam-hot during curing, then stripped and reused a dozen times. IS 4990:2011 (Plywood for Concrete Shuttering Work — Specification) therefore demands BWP (boiling water proof) phenolic bonding proven by boil testing, minimum glue shear strength retained after boiling, and specified static bending strength.
Global Lab verifies shuttering plywood against IS 4990:2011 using IS 1734 methods — 72-hour boiling water resistance, glue shear strength (dry and after boil), modulus of rupture and modulus of elasticity, moisture content and density — so contractors know a batch will survive its promised number of repetitions instead of delaminating in the second pour. The standard is also under the mandatory BIS certification regime for plywood products.
How the Shuttering Plywood Testing is Conducted
- 1
Sampling & Conditioning
Sheets are sampled per IS 4990 rules; specimens for each test are cut and conditioned per IS 1734 requirements. - 2
Moisture Content & Density
Oven-dry moisture content and density are determined and checked against specification limits. - 3
72-Hour Boiling Water Resistance
Specimens are boiled for 72 hours and examined for delamination — the defining BWP bond-quality test for shuttering grade. - 4
Glue Shear Strength
Shear specimens are tested dry and after the boil cycle; retained strength must meet the IS 4990 minimums. - 5
Static Bending (MOR / MOE)
Modulus of rupture and modulus of elasticity are determined along and across the grain per IS 1734. - 6
Reporting
All results with an IS 4990:2011 compliance verdict are issued via Autovity QLMS.
Applicable Test Standards
| Standard | Title | Scope | Type |
|---|---|---|---|
| IS 4990:2011 | Plywood for Concrete Shuttering Work — Specification (Third Revision, Reaffirmed) | Product Specification | Indian Standard |
| IS 1734 (Pts 1–20):1983 | Methods of Test for Plywood (Reaffirmed) | Test Methods | Indian Standard |
| IS 848:2006 | Synthetic Resin Adhesives for Plywood (Phenolic and Aminoplastic) — Specification | Adhesive Reference | Indian Standard |