SU1219700A1 - Method of restoring asphalt concrete - Google Patents

Description

1.12

The invention relates to a technology for repairing pavements, in particular, the restoration of old asphalt concrete, and can be used to prepare an asphalt concrete mixture from new materials.

 The purpose of the invention is to improve the mechanical properties of the asphalt concrete to be restored.

The method is carried out in the following sequence.

In the restored area of the asphalt concrete pavement, grinding is first carried out and then heated, for example, in a stationary installation of the coating layer to be repaired, and in the heating process, the layer is subjected to low-frequency vibrations directed in its plane with a frequency of 50 to 600 Hz. changing the direction of their effect on .90.

In the initial period, the effects of low-frequency oscillations are distributed over the restored portion of bitumen with surface-active regions, and the duration, the period of exposure to oscillations in one direction, is 2.5-5.0 minutes.

The duration of vibration in one direction was chosen on the basis of experimental work on the heating of asphalt concrete by the temperature difference at points located 200 mm apart from each other. With vibration heating, this difference is 2.5 ° C with a vibration time of 1 minute; 1.5 C at 2.5 min; 1 C at 5 min. A further increase in the vibration time np gave a decrease in the temperature difference at the indicated points. Without vibration, the temperature difference is 3 ° C.

Regarding the frequency of vibration in the limit.x from 50 to 600 Hz, this range is most common in road construction equipment. It is well tested and does not adversely affect people and the environment.

The use of low-frequency vibration during heating of the restored layer by an electromagnetic high-frequency field allows the particles of the heated material to move in the layer, which contributes to the uniform effect of the energy minima and maxima on each particle in pe002

As a result, this provides a more uniform heating of the asphalt concrete with its compaction.

The introduction of bitumen with surfactants during vibration effects contributes to its more uniform distribution among the particles of reduced asphalt concrete and intensifies the process.

adhesion.

Example. An old asphalt layer was removed from the road section, delivered in a pallet truck and placed in a heating chamber, which is insulated from radiation into the surrounding medium and grounded. Then, a high-frequency electromagnetic field generator is turned on, and a plate forming a working capacitor is placed above the asphalt concrete of a grounded truck. Simultaneously with the start of asphalt concrete heating, the vibrating device with a frequency of 50 Hz is switched on. In the initial period of exposure to fluctuations in the treated

asphalt concrete makes bitumen with surface-active additives.

Every 2.5 and 5 minutes, the direction of the vibration effect in the plane of the asphalt concrete layer on the pallet of the trolley changes by 90. The change in the direction of vibration is carried out before the formation of an asphalt-concrete mixture with an operating temperature of 135 ° C. After this, the impact of the electromagnetised floor and vibration is turned off, and the asphalt concrete mixture thus restored is moved to the place of its laying.

At the same time, asphalt concrete mixture is prepared from new materials and old asphalt concrete is restored by a known method. The results of testing samples from different mixtures of asphalt concrete

are shown in the table.

Continuation table

The index of the tensile strength of the recovered asphalt on the previous

as it can be seen from the table, it exceeds the rate of reduced asphalt road, the tone by a known method and approaches the strength of the newly prepared mixture.

The application of the proposed method in practice as compared to the known one allows, through the use of low-frequency vibration during electromagnetic heating, to increase the heating uniformity of asphalt concrete and improve its mechanical properties, bringing them closer to the properties of new asphalt concrete, while the production volume of the latter can be reduced with a corresponding material saving. and energy.

Claims (1)

'METHOD FOR RESTORING ASFKHCHETOBETON, including the distribution of bitumen with surface-active additives on the reconstructed layer of asphalt concrete, heating the latter with a high-frequency electromagnetic field, grinding and mixing of asphalt concrete with bitumen and surface-active additives, characterized in that, in order to increase the mechanical properties of asphalt, during heating, asphalt concrete is subjected to directional low-frequency oscillations with a periodic change in their direction action in the plane Q of the treated layer is 90, grinding of asphalt concrete is carried out before its heating, and the distribution of bitumen with surface-active additives is carried out in the initial period of exposure to low-frequency vibrations, and the duration of the period of exposure of the latter in one direction is assumed to be 2.5-5 minutes. SU 1219700> As a result, this ensures more uniform heating of asphalt concrete with its compaction. The introduction of bitumen with surface-active additives during vibration exposure contributes to a more uniform distribution among the particles of restored asphalt concrete and adhesion. The main road of the concrete, don, and placed in a heating chamber, which is insulated from radiation into the environment and grounded. Then a high-frequency electromagnetic field generator is turned on, and a plate forming a working capacitor is placed above the asphalt concrete of the grounded trolley. Simultaneously with the start of heating of asphalt concrete, a vibration device with an oscillation frequency of 50 Hz is turned on. In the initial period of exposure to vibrations, bitumen with surface-active additives is added to the asphalt treated. After every 2.5 and 5 minutes, the direction of the vibration effect in the plane of the asphalt concrete layer on the pallet of the trolley changes by 90. The direction of vibration is changed before the formation of an asphalt concrete mixture with an operating temperature of 135 ° C. After this, the influence of the electromagnetic field and vibration is turned off, and the asphalt mixture thus restored is moved to the place of its laying. At the same time, the preparation of the asphalt mix from new materials and the restoration of old asphalt are carried out by a known method. The test results of samples from different mixtures of asphalt concrete are given in the table. I intensifies the process