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There are many preparations before concrete paving. We mainly emphasize the unloading process of sprinkler before concrete paving.

(1) Sprinkling before paving is a seemingly simple process, which is often ignored by the construction personnel, but if the sprinkling water treatment is not good, it will seriously affect the quality of the road surface.

The amount of sprinkler should be determined according to many factors such as base material, air temperature, humidity, wind speed, etc. That is to ensure the wetness of base before spreading concrete, and sprinkle evenly as possible, especially where the base is uneven, the phenomenon of water storage is forbidden. From the point of view of the current construction site, most of the cases are insufficient water sprinkler, because the base is dry, a large number of small cracks occur at the bottom of the concrete pavement after paving, and some small cracks overlap with the cracks caused by the shrinkage stress of the concrete itself, which increases the cracks of the whole concrete pavement.

(2) The unloading of dump trucks is also a process that is often neglected. In construction, too much material in front of the paver often makes it difficult for the paver to walk. Sometimes too little material makes the amount of concrete in the tamping box insufficient, and the thickness of the pavement can not be guaranteed. In front of the paver, this phenomenon of excessive or insufficient concrete will seriously affect the evenness of the concrete pavement.