Dust removal
In road construction, dust clearance is taken to mean measures to remove dust from unbound roads and paths. The measures are largely limited to treating the road surface.
Starting position
The term originated in the early days of modern road construction, when sand-muddy gravel roads were the rule both in the city and in the country (around the middle of the 19th century in Europe). This so-called macadam construction was easy and inexpensive to manufacture, but it also had the disadvantage of annoying dust development. With the advent of motorized traffic, the problem got even worse, as more dust was blown up underneath the vehicle due to the higher driving speeds and the associated suction effect. This led to massive annoyance for passers-by as well as to an emaciation of the macadam surface. It was therefore decided to make the streets (as far as possible) free of dust.
activities
A well-known measure for combating road dust was to moisten the road or path surface. With the help of a blasting vehicle , water was applied over a large area and thus the fine grains of dust were bound for a short time. However, this type of dust control was not particularly permanent. For example, it was reported that the road from London to Bath had to be watered daily during the summer. The effect could be improved by adding hygroscopic salts ( e.g. anti-dustite ) to the water, which caused crusts to form on the road surface.
Shortly after the introduction of the macadam construction method, various attempts to bind the dust had already been made in several cities in Europe . However, the breakthrough came after the turn of the century. The Swiss doctor Ernest Guglielminetti founded the "League against Dust" ( French Ligue contre la poussière ) in 1901 and also made experiments with dust-binding agents. He paid particular attention to avoiding damage to health. It was believed that raising dust promoted the spread of diseases such as tuberculosis . In 1902 he used viscous tar for this purpose , a cheap and readily available waste product in the production of gas from hard coal, and passed it on a gravel road in Monte Carlo . The road paved in this way was able to withstand the stresses of traffic and weather significantly better and did not allow any dust to develop. As a result, surface taring quickly spread and was used to pave many urban and rural roads in Europe. As a result, there were also further developments, such as the distillation of the tar to produce higher quality road tar and the complete impregnation of the gravel road (so-called drinking macadam ).
Further developments
After the Second World War, in particular, the removal of dust by means of spraying, brushing on or soaking bituminous binders was increasingly promoted in Europe. Dust-free programs have even been set up to get the highways back into a better condition as quickly as possible. Until 1960, for example, most of the West German federal highways had a bituminous cover.
However, due to the constantly increasing number of vehicles and the simultaneous increase in axle loads, it soon became apparent that even roads with surface boundaries could not withstand the loads in the long term and that the removal of dust and its surface treatment was only an intermediate stage. In order to meet the requirements of modern road traffic, extremely viable and durable asphalt construction methods were developed in the period that followed, and measures to remove dust were finally abandoned entirely.
Individual evidence
- ^ Maxwell G. Lay: The History of the Road . Campus Verlag, 1994, ISBN 3-593-35132-3 , pp. 221 .
- ^ Lueger, Otto: Lexicon of the entire technology and its auxiliary sciences, Vol. 9 Stuttgart, Leipzig 1914., pp. 752–753
- ^ Johannes Kastl: Road construction . BG Teubner Verlagsgesellschaft, 1968, p. 19 .
- ↑ Werner Hoppe: The intermediate expansion - a successful method for the rapid modernization of the road network , published in Bitumen , 1991 edition ( online )