Geotextile is widely used in many fields, such as water conservancy engineering, construction engineering, landfill, highway construction and so on.  let's learn about application of geotextile road paving.

Old pavement treatment

1.The old highway surface shall be cleaned of dust, loose particles and sundries, and the surface shall be kept dry. The sharp and abrupt parts of the road surface shall be leveled; the severely damaged and broken parts of the road surface shall be removed and repaired with asphalt concrete. For the pavement with serious cracks or ruts, a 1-2cm leveling layer shall be paved.

2.Spray asphalt tack coat oil

When liquid petroleum asphalt is used as tack coat oil, the atmospheric temperature is above 5 ℃; when emulsified asphalt is used as tack coat oil, the atmospheric temperature is above 10 ℃. When the road surface is wet in rainy days and after rain, the tack coat oil shall not be poured. Pay attention to the selection of the type and quantity of the tack coat oil. It has been proved that it is better to use the asphalt modified by EVA or SBS. These products have good crack resistance and thermal stability. If emulsified asphalt is used, its asphalt content must be more than 60% to make good use of.

Before the geotextile is laid, the asphalt tack coat shall be sprinkled once for pumping, the amount of which is about 0 ·4 ～0 ·6kg / m2, then the geotextile shall be paved, and then the same type of tack coat oil shall be sprinkled on the geotextile, the amount of which is about 0 ·5 ～0 ·6kg / m2. Attention should be paid to the following points:

(1) it is recommended to use hot asphalt tack coat sleeve, and the oil temperature should be kept between 150-170 ℃;

⑵the horizontal range of spraying tack coat oil should be 5-10cm wider than that of geotextile;

(3) the spray of tack coat oil should be uniform, and the measurement should be accurate.

If the primary oil pouring is adopted, the total amount of the adhesive layer oil cannot be reduced. The recommended value is 1 ·0~1 ·3kg/m2, and the oil temperature cannot be lower than 180 ℃. It is easy to appear that geotextile is impervious and layered in one time oil pouring, which leads to the phenomenon of surface peeling.

Laying and lapping of Geotextile

1. It is better to use mechanical erection or manual laying for geotextile. When laying, pay attention to make the rough side of the singeing face up, and then fix one end with a fixer, tighten it with machinery or manpower, with an elongation of about 1 ﹤0% ～1 ﹤5%, and lay straight and close to the road.

The fixer includes a fixing nail and a fixing iron sheet. The fixed nails should be cement nails or shot nails with a length of 8-10cm; the fixed iron sheet can be made of iron sheet strips with a thickness of LMM and a width of 3mm.

2. The transverse lap of geotextile is about 4-5cm. According to the paving direction, press the back end under the front end, and use hot asphalt or emulsified asphalt to bond well, and fix it with fixer; the longitudinal lap is also about 4-5cm, which can be dried with bonding oil directly. If the lap joint is too wide, the interlayer at the lap joint will become thick, and the binding force between the surface layer and the base course will be weakened, which will easily lead to adverse effects such as bulge, separation and displacement of the surface layer. Therefore, the part with too wide overlap should be cut off.

3. The geotextile shall be laid in a straight line as far as possible. When it is necessary to turn, cut the bending part of the fabric, lay it on top of each other and spray the adhesive layer with oil. Fabric wrinkling shall be avoided as far as possible. If wrinkling occurs during laying (when the height of wrinkling is more than 2cm), the part of wrinkling shall be cut, and then the laying direction shall be overlapped again, and the joint shall be made with adhesive layer oil.

4. When the geotextile is laid, spray the asphalt tack coat oil for the second time and cool it for about 2 hours, and then spray a proper amount of fine yellow sand in time to prevent the cloth from being taken up or damaged by the wheel tack oil when the vehicle passes the geotextile, and the amount of fine sand is about 1-2kg / m2.