Do you know that road maintenance in winter is the alchemy?
The past in the name of slag
In the past, roads in winter were gritted with anything, slag from boiler and heating plants, in particular. At the time nobody cared about the negative impact it had on the environment. Moreover, it was an easy solution which did not require any costly equipment or processes.
With further development, and increased traffic and demands of drivers for passable roads, new road maintanance materials were introduced.
New materials for road maintanance
Materials for winter road maintenance are divided into the following categories:
-
abrasive
- stones and sand up to 8mm in size (inert material),
- sand (grains of 2–4mm) is used for icy surfaces,
- bigger size material is used for snow-covered surfaces;
-
chemical (de-icing)
- sodium chloride – used at the temperature of about -5°C and becomes ineffective when the temperature exceeds -8°C,
- calcium chloride – used at the temperature of about -15°C,
- mixture of both substances – used between -8°C and -15°C.
In built-up areas the mixture of inert and chemical materials in the ratio of 5:1 has proved effective.
Advantages of abrasives:
- they can be used in any weather and temperature conditions,
- they are effective immediately, especially on icy surfaces at low temperatures.
Disadvantages of abrasives:
- they must be cleared in spring,
- they block the sewerage system in spring when snow melts.
Advantages of chemicals:
- ice or snow can be cleared completely; no material left to be cleared in spring.
Disadvantages of chemicals:
- they are not effective at temperatures below -15°C,
- their effect on the environment is uncertain .
Road maintenance is the alchemy and no matter what we do, somepeople will still say: „Winter has caught them by surprise once again.“
