Procalm - A Hot Applied High Friction Anti-Skid System
Procalm is a hot screed applied polymer modified rosin ester material, designed
for use with various types and grades of bauxite aggregates. It can be supplied
for use in Red or Green coloured surfaces, although others colours are available
Procalm is less weather sensitive than epoxy based systems and can therefore be
applied all year round on new or worn surfaces.
It can be readily applied to all asphalt surfaces and can also be used on
concrete surfaces after preparation with a suitable primer.
Procalm is used for applications where a textured durable matrix of 3 - 5mm is
required which meets the NRA requirements for skid resistance and texture depth
- application such as:
- Village Gateways
- Speed Roundels
- Ghost Islands
- Bus Stops
- Cycle Lanes
Procalm is supplied in 25-kg low melt polythene sacks.
Softening Point: Minimum of 90oC when tested to BS 2000 Pt 58: 1993
Flow Resistance: Maximum of 1% when tested to BS 2499 Pt 3: 1993
Standard Red or Green with other coloured grades available on request.
Washed and dried graded aggregate with a PSV of 65 and a moisture content of
less than 1%. Coloured aggregate incorporated into the material should not be
less than 100% of the overall typical aggregate content. The aggregate content
of the mix is typically 55%. Table 1 shows the grading information for the mixed
aggregate and extender.
The surface should be treated using a hot compressed air lance operating at
800oC to remove dust, laitance and foreign matter. Unless otherwise directed,
all existing road markings, iron work and road studs should be suitably masked.
Procalm should be loaded into a heater/mixer with positive temperature
control and mechanical agitation via horizontal hydraulically driven stirrers.
Application temperature is typically 190°C +/- 10°C.
The hot material is poured into a screed box with a suitably designed trailing
edge and is applied by combing transversely across the surface of the site.
This allows the aggregate to be evenly distributed to provide a well textured
(average TD 1.5 +/- 0.1mm), durable skid resistant surface with a minimum Skid
Resistance Value (SRV) of 65 when measured by the Portable Skid Resistance
Apparatus. On the average TD surface the coverage rate of the material should be
10.5 - 11.15 kg/m² (85 - 95 m²/tonne).
A rougher surface may require a higher rate of spread. After completion, the
surface should not be opened to traffic until it has reached the temperature of
the adjacent road surface, typically 20 minutes.
Table 1 Aggregate Grading
|BS Sieve Size
||90 - 100 %
||65 - 95 %
||40 - 55 %
||25 - 45 %
||5 - 15 %