Plastic runways are used in schools, professional stadiums, track and field runways, semi-circular areas, auxiliary areas and national fitness paths. However, when building a plastic runway, there are some things to pay attention to:
1, build the environment in strict accordance with the requirements of the product. Generally speaking, the plastic runway has a large area and a long construction period. Therefore, we must make a good construction plan, arrange the construction time reasonably, and take good cold protection measures.
2, check the local weather forecast before construction, formulate the appropriate construction scheme. When laying rubber surface, be sure to master the weather conditions and take emergency measures to prevent showers.
3, before laying the plastic runway, to do a good job at the grass-roots level, including removing dust, oil and loose substances on the surface of the grass-roots; Reduce or eliminate surface defects; Improve the physical or chemical properties of the base surface.
4. In cold weather, plastic runway materials should be classified and stored indoors, and the indoor temperature should be above zero. When the temperature is below zero, heating or electric heating should be used to raise the indoor temperature.
5, plastic runway material allocation must be accurately weighed in proportion and stirred evenly. Before using each barrel of materials, the whole barrel of materials must be stirred evenly before batching.
6. In the construction process of polyurethane plastic materials, I am most afraid that water and mucilage will produce big bubbles when they encounter a drop of water before initial setting. Therefore, when working under high temperature in summer, construction personnel should prepare towels to wipe sweat.
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Construction scheme flow of plastic sports ground
Plastic playground is a playground paved with plastic track. Its construction technology is: foundation excavation, leveling and compaction → 12% lime soil (300mm thick) construction → hot bonding →SBS waterproof layer → C25 concrete layer → 150mm thick → plastic bottom pavement → plastic surface pavement. Here is a detailed introduction to the construction technology:
1. Foundation excavation shall be leveled and compacted.
According to the design elevation of the site, excavate the foundation, level the site manually and mechanically, and roll it with a 20t vibratory roller. When the vibratory roller rolls, the dynamic and static pressure should be weak first and then fast, and weak first and then strong. It is required that there is no pressure leakage and dead angle after construction, so as to ensure uniform rolling, smooth and solid surface, no obvious wheel tracks, no soft elastic and boiling, good drainage and compactness meeting the design requirements.
2. 12% lime soil (300mm thick) structure
(1) Measuring unreeling, according to the construction width of lime soil, the actual width is 50cm wider than that of lime soil base, so as to ensure the compaction quality of base.
(2) Use an excavator to apply soil, which is roughly evenly distributed according to the thickness of 17cm.
(3) The digested lime is transported to the construction site with loaders and dump trucks, and packed with pre-calculated yards. After acceptance by the supervisor, it will be released manually.
(4) The lime-soil test section shall control the elevation according to the parallel lines of the road surface, first flatten it according to the filling height, then measure the elevation, measure 3 points every 10cm road surface section, then pull the leveling bar, put a small amount of lime with obvious signs, and the grader shall level it carefully by manual trimming.
(5) Mixing: In the mixing process, if the water content of lime soil is insufficient, sprinkler should be used for supplementary sprinkling. After sprinkling water, it should be stirred again to make the water evenly distributed in the lime soil. Mixing machinery should be followed closely behind the sprinkler for mixing, so as to reduce water loss.
3, SBS waterproof joint thermal bonding
(1) requires the surface of the base to be dry, and its moisture content shall not exceed 8% according to the regulations, or the surface shall be smooth through the covering bonding test, so as to ensure that the base is hard and free from sand, cracks, looseness, bulging and inequality. Check the surface leveling with a 2m-long ruler. The gap between the ruler and the base is no more than 5mm, and only a gentle change is allowed. There is no water on the surface, and the waterproof layer construction can only be carried out after the drainage slope meets the design requirements.
(2) Clean up the qualified base, and spray the treatment agent on the base, requiring the treatment agent to be sprayed evenly. After being treated and dried at the grass-roots level, waterproof coiled materials can be laid.
(3) Waterproof coiled material shall be laid in parallel or perpendicular to the roof direction according to the requirements of the specification, generally from low to high in the direction of running water.
(4) The lapping of coiled materials shall be carried out according to the following steps: Ⅰ. Long-side lap: the longitudinal lap width of the coiled material is more than or equal to ≥80mm, and the single-layer waterproofing should be carefully operated. Firstly, the anti-sticking layer and granular protective layer on the coiled material to be overlapped are melted, and at the same time, the adhesive on both sides of the joint is melted, and then the adhesive is exhausted, compacted with a hand-held roller, and there are obvious asphalt strips. Ⅱ short-side lap: both ends of the coil must be fully bonded, and the lap width and single-layer width should be ≥100 mm. The coil should be positioned at the grass-roots level for elastic line and trial laying, and the laying scheme of the coil should be determined according to the coil specifications, laying requirements, roof drainage slope and detail size.
(5) The second waterproof construction technology is the same as the first one, but it should be noted that the stagger of the long-side joints of the upper and lower layers of coiled material is not less than 1/3 of the width, and the stagger of the short-side lap joints is not less than1.5m..
(6) After the coil is laid, the overlapping parts, ends and coil ends must be sealed, filled with sealing material, sealant or cold adhesive, and then smoothed to form obvious asphalt strips.
4, 150mm thick C25 concrete layer construction
(1) The concrete layer shall be constructed in strict accordance with C25 concrete mixture ratio standard, and the concrete shall be mixed on site. All raw materials should be mixed in strict proportion, and the mixing time of cement concrete should be strictly controlled.
(2) Preparation before pouring, including inspection of formwork and its supports, preparation and inspection of materials, machines and tools, etc. , and do a good job of construction organization and technical and safety disclosure.
(3) After concrete pouring is completed, the concrete surface shall be kept moist with sacks, and the cement concrete surface shall be watered in time to keep it moist all the time. Wet curing can be used in rainy season or when there is enough water for curing. The concrete surface is completely covered with moisturizing curing film, geotextile, sack, straw bag or straw curtain, and the bottom of the cover is always wet by sprinkling water several times a day. Generally, the days of health preservation should be 15 days, with high temperature days not less than 10 days and normal temperature days not less than 15 days.
5, plastic bottom construction
After the foundation meets the requirements, the plastic surface layer shall be laid. The plastic laying shall follow the construction process of "inside first, then outside", with two semicircles first, then the runway, and then the auxiliary area:
(1) After the construction team enters the site, use the calibrated theodolite to set out the location of the sports field, and retest the leveling points and elevation of the field to determine the construction scope of the plastic track pavement of the sports field.
(2) According to the design requirements of the site and the requirements of the plastic paving process of the site foundation, the site foundation shall be rechecked, including measuring whether the flatness and slope of the site meet the requirements of outdoor sports venues, and at the same time, the foundation must have enough curing period to pave the plastic surface.
(3) In terms of construction conditions, the water content is required to be lower than 8%, the air humidity is lower than 85%, and the temperature should be above 10℃.
(4) Semi-finished plastic materials should be sent to the construction site at one time according to the reported material plan, and the variety and quantity of materials should be counted before starting and picking.
(5) Before laying the plastic bottom layer, brush it evenly on the basis of asphalt concrete with special glue to enhance the bonding force between the foundation and the plastic surface layer.
(6) Then stir the materials, spread adhesive tape or plastic cloth on the place where the materials are stirred, then put them in a mixing barrel, and pour the materials into the mixing barrel in proportion for mixing. After the materials poured into the mixing barrel are stirred evenly by a professional mixer, an appropriate amount of catalyst is added to stir, and finally black particles are added in proportion to stir evenly.
(7) Laying the base course: Set up the construction line, frame the site to be laid with tape paper, and start laying the rubber compound. When applying the rubber compound, the rubber scraper should fill the exposed and concave parts in time, scrape the convex parts and ensure the smooth edges; The defoamer should be defoamed until there is no foam. If there are impurities in the glue, it should be removed in time to ensure that the glue surface is clean and scratch-free. At the same time, when laying the plastic bottom layer, the contact edges of the plastic surface layer, the inner ring ditch and the field events facilities should be wrapped.
(8) After the plastic bottom layer is laid, it will enter the curing stage at room temperature. During the curing period, nothing should be placed on the surface, and the surface must be kept clean and dry, and pedestrians or motor vehicles are not allowed to walk on it. It usually takes 24 hours to cure.
6, plastic surface pavement
Surface construction adopts mechanical spraying surface:
(1) mixing, conveying and feeding: the mixer pours the glue, EPDM rubber particles and color paste into the mixing barrel according to a certain proportion for stirring. After the mixture is mixed, the transport vehicle immediately transports the mixed mixture to the shotcrete machine, and then pours it into the shotcrete machine for spraying under the guidance of on-site technicians.
(2) Spray surface adhesive layer: the plastic surface layer should be made of colored plates, and the surface layer color should be bright, uniform, without spots and glare. After the selection, use the sprayer to spray three times in the forward direction, reverse direction and forward direction, and the spraying point should be 90 degrees. If raindrops fall, the spraying material should be sufficient at one time. When laying a plastic surface layer, the edge of the plastic surface layer in contact with the surrounding area should be wrapped.
(3) Normal temperature curing: the curing time is determined according to the construction temperature, and usually the curing time is 12-24 hours.
(4) Surveying and marking: use theodolite and steel tape to erect point lines, and all point lines must comply with IAAF regulations, including curve lofting, straight line lofting and runway point lofting.
(5) Standardized maintenance: The plastic surface of the sports ground shall be maintained after paving, and it can only be put into use after more than seven days.
The above is what Bian Xiao shared today, and I hope it will help everyone.