CPL Concrete Shuttering Plywood is manufactured from specific durable Gurjan hardwood (I.e. the logs are 80-90 years matured) bonded with high quality Phenol Formaldehyde resin conforming to IS: 848:1974. It is pressed under high pressure and temperature and treated in with specific preservatives of high retention conforming to IS: 5539:1969. It is therefore boiling water proof, dimensionally stable and ideal for a long lasting service.
Loading and Deflection
By taking the maximum permitted deflection as 1:270 (viz 1/270 of the span between the bearers), the following data gives the maximum loads per sq. mtr.
(a) When the face grain of CPL Resin Film Densified Wood plates is parallel to grain bearers.
| Centre distance to bearer | Loading (Kg./sq.m.) | |
|---|---|---|
| 9 mm | 12 mm | |
| 30 cm (12)” | 760 | 1220 |
| 40 cm (16)” | 320 | 540 |
| 50 cm (20)” | 195 | 390 |
| 60 cm (24)” | 110 | 170 |
(b) The face grain of the CPL Coated Plywood is perpendicular of bearers:
| Centre distance to bearer | Loading (Kg./sq.m.) | |
|---|---|---|
| 9 mm | 12 mm | |
| 30 cm (12)” | 1270 | 1950 |
| 40 cm (16)” | 540 | 850 |
| 50 cm (20)” | 320 | 640 |
| 60 cm (24)” | 170 | 360 |
The above loads apply when concrete is laid on CPL Concrete Shuttering Plywood as in slabs and beams. The same thickness of concrete in a wall can be held without excess deflection by using even thineer plywoods panels.
The maximum load shown above should be reducted to 75%, if wet boards used.
BENDING RADII
The minimum bending radil of CPL Concrete Shuttering Plywood When dry:
| Thickness | Across to grain of the outer ply | Parallel to the grain of outer ply |
|---|---|---|
| 6 mm (1/4") | 90 cm | 125 cm |
| 9 mm (3/8") | 165 cm | 215 cm |
| 12 mm (1/2") | 255 cm | 330 cm |