26.07.2010

German technology reveals new opportunities for the infrastructure projects in Varna, decreasing expenses for reconstruction of roads with about 40%. Today it was experimentally applied along “Atanas Moskov” street – in the section from “Kolyu Ficheto” street to the roundabout.
The technology “Atlas”, known abroad, is already used for asphalting roads in different parts of Bulgaria, mainly in Sofia district. It was also used for building 4 km of the motorway “Maritsa” – between town Svilengrad and Kapitan Andreevo, told Dimitar Irikov, chief engineer of the company “Atlas Balkan” which has introduced the new method in Bulgaria.
The method represents cold recycling, by which the old tarmac is demolished, processed and laid again. This technology, however, can be applied over the asphalted 30-40 m of the selected section along “Atanas Moskov” street. In the other more than 200 m from the assigned for repair pavement, the method will be used only for stabilizing the ready ground layer, explained eng. Irikov. The site was assigned to the company “Ingstroyengineering” and it will have the task to lay asphalt over the new covering in a few days. When it is done, the pavement life will be extended from 2-3 to 10 years, the investors assured us.
Practically when using the “Atlas” technology, hydraulic substance with polymer additive and water is added to the material, collected from the ground layer of the road. Bitumen can be used for the components of the stabilizing layer. The binding substance is cement base and it is produced in “Devnya cement”. The prescription about the exact proportions is worked out after examination of the material from the ground layer of the pavement in the laboratory for roads and bridges in the capital city. 18-ton steam-roller compacts the stabilizing layer, then grader passes over it, and a rubber roller smoothens and seals the surface, explained Dimitar Irikov. He added that the complete section of 240 metres along “Atanas Moskov” street shall be ready only for half a day.
Except the economic effect, which guarantees decrease of the expenses for asphalting with 30-40%, the technology also increases the elasticity of the pavements with 200%. At rate of construction, which allows processing of 500 metres per day, the strength parameters are phenomenal. The method guarantees that the ground layer will be impervious to water and will be sustainable to very low temperatures. Even at minus 20 degrees its structure will not change, added the engineer. Besides, the technology changes the thickness of the lowest layer of the road, decreasing it with about 50 %. Thus instead of being 20 cm, the ground layer of the pavement along "Atanas Moskov" street will be 10 cm thick, pointed out dipl. eng. Stoyan Dimitrov, chief of municipal division “Engineering infrastructure and public utilities”.
Only our company was ready to experiment, commented Hristo Furchev, chief of “Ingstroyengineering”. He expressed readiness to use the new technology if it proves to be efficient. According to the project there had to be only local repairs along "Atanas Moskov" street and the “Atlas" technology will allow complete reconstruction of the pavement – on both roadways, each of them with 2 lanes. And the expenses will increase very little in comparison with the value of the project, initially assigned by the municipality. The economical effect is doubtless, though the method is more appropriate for motorways than for city roads, where many shafts are available, added Mr Furchev. Instead of being driven away and disposed, the existing earth mass will be processed. It also saves expenses, estimated the chief of the company-executer. The results from the experiment in Varna will be analyzed and reported in a week.

Source: newspaper “Cherno more”, original title: /German technology saves 40 % of the money for roads"