Road doctor: ruts have a new prescription

Deformation of asphalt pavement, especially rutting, is a special disease type of asphalt pavement, which is closely related to temperature sensitivity of asphalt materials.

Rutting damage

Deformation diseases are bound to occur in the life cycle of asphalt pavement, sooner or later, and have become asphalt pavement “ Cancer & throughout; And high temperature and heavy load traffic are the two main causes of accelerating the deformation of asphalt pavement. Road workers mainly use modified asphalt and optimized mixture gradation to improve the anti-deformation performance of asphalt pavement, but they only delay the time of deformation and have little effect on heavy load and above traffic. For sections prone to heavy rutting deformation, such as level crossings, uphill sections, BRT lanes, port roads, etc., maintenance year after year has exhausted the custodians.

For & other; Effect a radical cure & throughout; Asphalt pavement deformation diseases, “ Road doctor ” After many years of technical breakthrough, research and development of targeted “ The new prescription & throughout; & ndash; & ndash; Large gap grouting asphalt pavement technology, and successfully applied in ldquo; Clinical trials ” .

2 technology introduction

Large gap grouting asphalt pavement technology is in the flexible large gap asphalt mixture (void ratio of 20%~30%) into the special high-strength slurry, the formation of “ The combination of hardness and softness ” The large gap grouting pavement, with beautiful and comfortable asphalt pavement and strength stability of cement concrete pavement, fundamentally solves the problem of asphalt pavement deformation diseases.

Advantages over asphalt pavement are as follows:

(1) the rutting resistance is more than 5 times that of traditional high-performance asphalt, and the rutting depth within five years is less than 5mm (see the figure below);

(2) better water stability, residual stability and freeze-thaw splitting ratio both exceed 90%;

Compared with the advantages of cement pavement are as follows:

(1) good plate performance, no need to cut seam in the whole process, low driving noise, good comfort;

(2) good surface flatness, large structure and good anti-slip performance;

(3) after opening to traffic, the color of the pavement can be adjusted according to the needs. It can be a striking color or the same color as the surrounding asphalt pavement.

3 application scope

This technology is applicable to heavy load and above traffic load sections, level crossings, climbing sections, BRT dedicated lanes, toll stations, ports, airports and other special heavy load rutted sections.

4 grout characteristics

The grouting grout used in this technique is composed of “ Road doctor ” Independent research and development, with the following performance characteristics:

(1) the strength is rapidly formed, and only 2~3h of health maintenance is needed to open the traffic (the following figure shows the data of compressive strength at different health maintenance times);

(2) low consistency, good fluidity, no need for vibration, perfusion rate can reach above 98%;

(3) no bleeding, high surface strength and good durability;

(4) different colors can be prepared according to the needs, which can be applied to colored pavement.

Color large gap grouting pavement core section

5 application case

(1) background

Chaohu S105 hejie road bantang street section, heavy traffic, heavy Vehicles, multiple intersections appear rutting disease, local rutting depth of more than 10cm.

State of original road surface

(2) on-site coring
On-site coring found that there was no damage to the left and right wheel tracks and the base course in the middle of the lane, and the ruts were mainly caused by the deformation of asphalt layer. (see the following figure for the core sample)

Core diagram of different parts of single lane

(3) maintenance scheme
Mill 10cm asphalt layer (middle and upper layer) of the original road surface within the damage range, spray emulsified asphalt adhesive layer oil, and then lay 10cm large void modified asphalt mixture (20%~30% void ratio) back, and pour special grout after the temperature of the mixture drops to the ambient temperature. After 3 hours of health maintenance, open traffic.

Pavement structure chart after grouting

(4) construction process
The construction process is as follows (from left to right) :

(5) effect evaluation
After the health maintenance, the pavement was tested and evaluated. The surface structure depth exceeded 1mm, and the core sample test results showed that the perfusion rate reached 98.4%.

Track and observe the rut development trend as shown in the figure below. By comparison, it can be seen that the rut developed to nearly 6cm in 1 year of operation of ordinary asphalt pavement at heavy traffic intersection, while the large gap grouting asphalt pavement had almost no rut.

Rutting trend chart of large gap grouting road and ordinary road

Site diagram

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