The function and construction method of adding geotextile when laying asphalt on highway​

 The function and construction method of adding geotextile when laying asphalt on highway

Geotextiles are widely used in highway pavement maintenance because of their ability to separate different materials, isolation, load sharing or reinforcement, and high tensile strength, puncture resistance and burst resistance. play a significant role. Asphalt laying on highway pavement is mainly combined with geotextile for three functions, namely maintenance and repair of asphalt pavement; old pavement covering to prevent pavement reflection cracks and delaying the occurrence and development of reflection cracks; providing highway subgrades to treat soft soil foundation, Accelerate the consolidation of the foundation and improve the bearing capacity of the roadbed.

1. Geotextile is used for maintenance and repair of asphalt pavement

Geotextile is an important pavement repair material. It can not only store enough impregnated asphalt to prevent water infiltration, but also has high strength, uniform structure, small shrinkage coefficient, strong toughness and large elongation. Ideal repair material.

Geotextile repair asphalt pavement construction method:

(1) When the road has cracks or cracks in different degrees, the geotextile can be cut into a certain shape, the size can completely cover the cracks and cracks, and each side should be 10cm wider. After cleaning the old road surface, the geotextile is impregnated with emulsified asphalt, spread on it, and then repaired with asphalt concrete.

(2) If the net is cracked, the crack area is large, or it has been formed into pieces, it can be treated by laying the geotextile as a whole, and the specific method is the same as above. The asphalt-impregnated geotextile can be changed to spray asphalt combined with oil, the geotextile is firmly rolled on it, and then a thin layer of asphalt is sprayed to increase the adhesion of the opposite layer and improve the waterproofness.

(3) If a paver is used to lay the asphalt concrete surface layer, it is not necessary to spray the surface layer asphalt, but only increase the amount of asphalt on the bottom surface, and control it to about 1000g/㎡. After rolling, the asphalt will penetrate the geotextile through its pores, reverse seepage to the surface layer, form a sealed waterproof layer, and also play a reinforcing role to improve the fatigue resistance of the new layer. Economical, convenient and durable.

2. Geotextiles are used for the prevention and treatment of pavement cracks

Geotextiles are used for the prevention and treatment of asphalt cracks in pavement. It is a common pavement repair technology to add asphalt surface layer on the old cement concrete pavement. It has the advantages of short construction period, low cost, little impact on traffic, and good service performance of road repair. However, the main problem is that reflection cracks are prone to appear in the asphalt overlay, and setting geotextiles is one of the main measures to delay reflection cracks.

The construction method of geotextile used for the prevention and treatment of pavement cracks:

(1) It is necessary to choose to lay geotextiles in high temperature weather. Before construction and laying, the road surface needs to be cleaned and cleaned.

(2) Laying geotextiles Geotextiles should be laid before asphalt cooling loses its cohesiveness. Geotextiles should be laid flat without folds and wrinkles. After laying, use tire rollers to roll them to make them tightly combined. The length of geotextiles is 15cm; Geotextile damage and paste is not good, it should be removed and re-paved.

(3) First, treat the old road surface and then spray 1.1kg/㎡ of petroleum asphalt on it. When laying the folds, it is necessary to manually flatten or brush the asphalt, and re-paste the folded places so that the upper and lower layers can be rolled after rolling. Geotextiles are bonded together. 214 The asphalt mixture should be paved immediately after the geotextile is laid, and the temperature should be controlled within 160°C. In order to facilitate the passage of construction vehicles, some sand should be sprinkled on the geotextile, and the asphalt mixture should be paved immediately after paving. Rolling until the requirements of the construction technical specifications are met.

Today, we mainly introduce the role of geotextiles in asphalt maintenance and asphalt crack prevention. The introduction of geotextiles for roadbeds is relatively high, and we will give you a detailed introduction in the future.

Summarize:

1. On the old cement pavement, first pave the lower layer of asphalt, and then lay the geotextile, which is convenient for leveling the old pavement and making the geotextile flat and sticky.

2. Adding asphalt surface layer on the old cement concrete pavement and laying geotextiles that meet the technical requirements can improve the smoothness and strength of the pavement.

3. Laying geotextiles can delay the occurrence of reflective cracks in cement concrete pavement.