Construction plan for fiberglass grating on asphalt concrete pavement
Construction plan for fiberglass grating on asphalt concrete pavement
Using crushed stone cushion layer for filling, the main construction process is: construction preparation → measurement and layout → removal of surface layer → 20cm thick cement crushed stone stable layer → graded crushed stone base layer → fiberglass grid → permeable layer → asphalt surface treatment sealing layer → 5cm thick asphalt concrete pavement → compaction inspection → handover acceptance.
ⅠCement stabilized crushed stone base
1 Road construction:
Roadbed filling and compaction operation: The filling material is laid, leveled, watered and moistened, and requires rolling and compaction after watering. The number of rolling passes is determined through testing. We plan to use the YZ-12T vibrating roller and adopt the forward and backward staggered method for construction. The width of the compaction track should not be less than 0.1m, and the driving speed during compaction should be 2km/h. The overlapping position shall not be less than 0.5m parallel to the road axis direction. When driving along the road axis direction, the edges and corners that cannot be reached by mechanical compaction shall be compacted using a 12 horsepower frog type compactor, and local manual wooden compactors shall be used for compaction.
After the construction of the road shoulder is completed, sand and crushed stone materials can be transported by car to the construction site for road surface construction. They can be manually transported to the on-site working surface for paving. The thickness of the paving should meet the design requirements, and then compacted with a vibrating roller.
The quality of crushed stone should meet the requirements of the specifications, and the grading should be good without any occurrence of particle size exceeding the standard. It should not contain stone powder, and the crushed stone should not contain wind fossils or soft stones.
Ⅱ Fiberglass grating
1. The effectiveness of fiberglass grating is closely related to the treatment of the road surface. Before laying, substances that may affect the bonding strength between the grating and the bottom layer, such as grease, paint, sealing materials, water stains, dirt, etc., must be thoroughly removed from the road surface to make the laying surface clean and dry. The pressure-sensitive backing on the fiberglass grille is a water-soluble substance. If there are water stains on the road surface, it should be laid after the road surface is dry. Before laying the grid, a layer of adhesive oil should be sprayed. If emulsified asphalt is used as the adhesive oil, the grid should be laid after complete emulsification and drying.
2. Laying and fixing of fiberglass grating
The grid laying can be carried out by specialized equipment modified by tractors or cars, or by manual laying. Before starting the laying, the adhesive surface should be selected downwards, and the above marked colors should be at one end to facilitate construction and avoid misplacing the adhesive surface. When laying the grid, it should be kept flat, tight, and not wrinkled, so that the grid has effective tension. After laying, it should be rolled again with a clean steel wheel roller.
Currently, there are two commonly used fiberglass grilles: with self-adhesive adhesive and without self-adhesive adhesive. Products with self-adhesive adhesive can be directly laid on a flat base layer, while those without self-adhesive adhesive are usually fixed with steel nails. The required materials for fixation are: ① 50 x 50 x 0.3mm fixed iron sheet, which is required to be flat and not warped, and the surrounding area should be chamfered; ② 2-inch steel nails.
When using the fixed steel nail method to lay fiberglass grating, first fix one end of the fixed iron sheet and steel nail on the lower structure that has been sprayed with adhesive layer asphalt, and the steel nail can be hammered or shot in. Tighten the grille longitudinally and fix it in sections, with each section length of 2-5m. It can also be segmented according to the spacing between contraction joints, with steel nails placed at the joints. Require the fiberglass to be in a straight and tensioned state in both longitudinal and transverse directions when the grille is tightened.
The grid overlap is a longitudinal overlap, with an overlap width of no less than 20cm and a transverse overlap width of no less than 15cm. The longitudinal overlap should be placed on top of the previous one according to the direction of asphalt paving. When fixing, the steel nails should not be nailed to the fiberglass, and the fiberglass should not be directly struck with a hammer. If the steel nails are found to be broken or the iron sheet is loose after fixation, they need to be re fixed. After the fiberglass grating is laid and fixed, it must be moderately compacted and stabilized with a rubber roller roller to ensure that the grating is firmly bonded to the original road surface.
In actual construction projects, the fiberglass grating is directly laid after spraying adhesive layer oil, and the roller follows closely to compact it. The effect is good, and the fiberglass grating is also not prone to waves.
Ⅲ Construction precautions
1.Strictly control the entry and exit of vehicles transporting mixed materials, and prohibit vehicles from turning sharply, braking sharply, and pouring mixed materials on the grid layer to prevent damage to the fiberglass grid.
2.Fiberglass grating adhesive is easily soluble in water, and construction should not be carried out on rainy days or wet roads.
3. Fiberglass grilles are made of fiberglass and are prone to irritating effects on human skin. Construction personnel must wear protective gloves.
4.When the rubber tire roller used needs to be filled with water to increase its weight, the amount of water injected should not be too full to prevent overflow onto the fiberglass grille, causing its back and abdomen to lose stickiness.
5.During the laying process of fiberglass grating, if it is found that there are small pits on the original road surface that have not been filled first, the corresponding part of the pits can be cut off on the laid grating, so that the pits can be completely filled when laying the upper layer of asphalt mixture.
6.When laying the grid, the road surface temperature is required to be between 5 ° C and 60 ° C.
Ⅲ Medium grained asphalt concrete
1. Asphalt concrete paving:
① Using a paver with automatic adjustment of paving thickness and leveling device to lay asphalt concrete. The road surface is paved in half width.
② When the radius of the curve is too small to operate with a paver, manual paving can be used. But it should be noted that the paving material should be unloaded on the iron plate; Use a shovel to pave, and do not lift the shovel far away; Spread and level with a scraper at the same time; The paving tools used should be heated for use.
③ The paving temperature of asphalt concrete: When using petroleum asphalt, the normal construction paving temperature is 110-130 ° C, and the maximum should not exceed 165 ° C; The low-temperature construction paving temperature is 120-140 ° C, and the maximum temperature should not exceed 175 ° C. When the temperature is below 5 ° C, asphalt concrete paving operations shall not be carried out. Reliable measures such as increasing the mixing temperature of asphalt concrete, strengthening insulation, and close coordination between paving and rolling must be taken. However, the mixing temperature of asphalt concrete shall not exceed the limit value specified in the specifications.
④ When paving, if it rains, the construction should be stopped, and the unloaded asphalt concrete should be well covered and insulated.
2. Asphalt concrete joints:
① The construction joint adopts the cold joint method. No longitudinal seams are left.
② The setting and jointing of horizontal construction joints. Sprinkle a layer of sand tape at the end of the predetermined paving section, and then lay the asphalt concrete and roll it into a slope. After cooling the asphalt concrete, use a cutting machine to remove the loose sand. The compaction of newly laid asphalt concrete at the transverse joint shall be carried out by transverse rolling first.
3. Asphalt concrete rolling
① The compaction of asphalt concrete adopts a combination of steel drum static pressure roller and vibrating roller for compaction, which is carried out in three stages: initial compaction, re compaction, and final compaction. The roller should roll at a slow and uniform speed.
② The rolling temperature of asphalt concrete: When petroleum asphalt is used, the normal construction rolling temperature should not be lower than 110-140oC; The rolling temperature for low-temperature construction is 120-150 ° C and shall not be lower than 110 ° C. The temperature at the end of rolling shall not be lower than 70 ° C. The initial compaction should be carried out at a higher temperature, but it should be determined based on the trial laying and compaction to ensure that there is no displacement or cracking during the compaction process.
③ The initial pressure is static pressure. The roller rolls from the outside to the center, with adjacent rolling belts overlapping by 2/3 of the wheel width. When rolling, the driving wheel of the roller must face the paver; Do not suddenly change the compaction route and direction; The starting and stopping of the roller must be done slowly at a reduced speed. The re compaction is carried out using a vibrating roller for 4-6 passes (determined based on experiments), with a vibration frequency of 35-50Hz and an amplitude of 0.3-0.8mm. The road surface should be turned, turned around, or parked for waiting.
