1. Pathology and causes of highway asphalt pavement diseases
1, types of highway asphalt pavement diseases
The disease of highway asphalt pavement is a general concept, because asphalt pavement has its inherent defects, and it is easy to produce diseases when the external conditions change after it is put into use. For example, under the influence of outdoor air humidity and temperature changes and the pressure of vehicle external force, asphalt pavement is prone to deformation, looseness, flooding, cracks, rutting and other diseases. When the asphalt pavement has initial pathology, if it is not maintained in time, it will lead to more serious diseases such as subsidence, potholes and frost boiling, which will directly affect the use value of the highway.
2. Causes of highway asphalt pavement diseases
The paving of highway asphalt pavement is a complicated process, and the appearance of highway asphalt pavement diseases is directly related to many factors in the initial design and later operation, so the appearance of highway asphalt pavement diseases is related to the following factors:
① The initial structural design is unreasonable.
In the preliminary design and demonstration of asphalt pavement, the proposed asphalt pavement structure design is unreasonable, and the selection specification of mixture is large. According to the design and construction requirements of specifications, in order to ensure the long service life of asphalt pavement after it is put into use, asphalt pavement should be designed and laid in a standardized way. In addition to considering the basic driving needs, we should also eliminate the influence of other bad weather, such as rain erosion and impermeability. It is more suitable to choose the mixture with smaller particle size and smaller gap for construction, and try to use fine-grained asphalt materials. For asphalt pavement with large diameter or semi-open graded asphalt macadam, waterproof sealing layer must be added during construction to prevent rainwater infiltration. In addition, the design thickness of pavement is not up to standard, which is also one of the important reasons for the diseases of highway asphalt pavement.
(2) The influence of overloading of running vehicles.
Overload has become a major problem in modern transportation. With the frequent occurrence of overloading and serious overloading of vehicles, overloading of vehicles has become one of the main factors of asphalt pavement diseases in China. In order to protect their own interests, some enterprises ignore laws, regulations and social benefits, resulting in extremely negative external effects, mainly reflected in asphalt pavement diseases.
③ Influence of pavement construction and maintenance management.
In the process of grass-roots construction, the surface cleaning is not thorough enough. Under the action of rain, these residual floating dust can easily soften fine materials and be washed and spread to the surface of highway asphalt pavement. For pavement construction, if the proportion of selected raw materials is not controlled enough, asphalt pavement diseases will occur.
Some maintenance personnel lack relevant knowledge and training. When maintaining asphalt pavement, they use manual oil spraying and manual paving, which directly destroys the smoothness of the original pavement and easily causes diseases such as looseness and accumulation.
Second, the highway asphalt pavement disease treatment methods
Different types of highway asphalt pavement diseases have different treatment methods. This paper puts forward specific treatment measures for the following different diseases.
1, treatment measures of rutting disease
Rutting is a common disease in highway asphalt pavement, and different methods should be adopted to remedy it according to the rutting depth. When the rutting depth is less than 10mm, and the connectivity between the base and the pavement is good, hot drying, harrowing, filling and other methods can be adopted to achieve the effect of repairing rutting diseases at high temperature. For severely damaged ruts, that is, the depth is greater than 10mm, and the connectivity between the base and the road surface is poor, which has affected the use of roads, the remedial method of removing heavy pressure should be adopted in time, and the thickness of ruts removed should reach at least 4 cm of damaged asphalt pavement. After the sundries and ups and downs are removed, the mixture matched with the original design is paved, and finally it is leveled by mechanical rolling.
2, crack disease treatment measures
According to the severity of cracks, different methods are adopted to deal with them. Small width. Generally, cracks less than 3mm can be made up with correction glue, which can be timely until further water phenomenon occurs; For cracks with a width greater than 3mm and a general width of 3-5 mm, the sundries and dust in the cracks must be cleaned first, and then poured with heated asphalt, and the speed must be controlled very slowly until the asphalt fills the whole crack. Finally, sprinkle materials for sealing and waterproof treatment. In addition to the above methods, you can also fill fine hot asphalt materials with manpower, seal them with road soldering iron, and finally take waterproof measures.
3. Treatment measures for pit and groove diseases
The scope of pit and groove repair needs to be square, and the surrounding lines should be vertical or parallel to the central pavement line. The repair of pits and grooves should be at least 10- 15cm larger than the actual damaged area. When excavating, it is necessary to ensure that it is carried out along the determined peripheral lines, and all the diseased parts should be removed, and all the wastes and residues should be cleaned up, and then the bottom and periphery of the excavation should be covered with sticky asphalt, and finally selected. In the process of backfilling, it is necessary to push from the edge to the center, and at the same time ensure that the backfill mixture is compacted layer by layer with the progress of backfilling, so as to ensure that the compaction degree meets the requirements and standards of highway grade.
4. Disposal measures of oil-soaked diseases
When the flooding disease of highway asphalt pavement is light, use a heating tool to clean up the spilled oil, and then flatten it with stone chips. However, when the asphalt pavement is seriously flooded, it is necessary to eradicate the disease, repair it with materials with smaller diameters, and finally compact it with machinery.
Three, highway asphalt pavement disease treatment technical advice
In view of the analysis of the above-mentioned diseases and remedial measures of highway asphalt pavement, this paper puts forward the following suggestions on the treatment technology of highway asphalt pavement diseases in China:
1. Highway asphalt pavement belongs to flexible pavement. In reality, the application of flexible asphalt pavement theory to guide semi-rigid base pavement lacks systematic experimental verification, which leads to different understanding of asphalt pavement thickness in theory and practice. Therefore, in concrete practice, we should use scientific theory to guide actual construction.
2. In practice, the statistics of traffic flow are irregular, which makes it easy for overloaded vehicles to destroy asphalt pavement. In the actual statistical work, it is necessary to fully estimate the traffic volume of specific roads and heavy trucks, rationally plan and design the bearing capacity of roads, and strictly control them from the initial laying to ensure the normal service life of roads.
3. In reality, construction is often divorced from reality, and builders often fail to meet the quality requirements of the original design. Therefore, strict control should be taken in the construction process to ensure that the goal of highway engineering construction can be realized. 、
4. The treatment of asphalt highway pavement should pay attention to early detection and maintenance to avoid more serious diseases in the later stage due to early neglect. Early treatment can undoubtedly save cost and time and avoid traffic accidents.
5. In the treatment of highway asphalt pavement diseases, there is often a lack of overhaul design standards. Therefore, in order to achieve the maintenance effect, it is necessary to evaluate the treatment technology and feed back the relevant effects to ensure the long-life service of asphalt roads.
Four. conclusion
High-quality highway asphalt pavement is very important to our production and life now, which is related to the safety of transportation. Its use safety is an important guarantee for the rapid development of national economy and the safe travel of people. In practical work, we need to make clear the mechanism and types of pathology, and improve the actual activities to ensure better technical treatment of asphalt pavement.
For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd