1, the height of formwork shall be consistent with the design thickness of concrete slab. When the thickness is less than 22cm, it can be poured at one time; When the thickness is greater than 22cm, it can be poured twice, and the thickness of the lower part is 3/5 of the total thickness. It is strictly forbidden to sprinkle water and cement on the surface just finished.
2, tamping should start from the corner. First, vibrate with an internal vibrator, and the continuous vibrating time for each place shall be no less than 20s；; Then fully vibrate with a flat vibrator, and the vibrating time at the same position shall not be less than 30 s.
3, longitudinal joint (longitudinal contraction joint and longitudinal construction joint) tie rod should be located in the center of the thickness, close to the transverse joint tie rod spacing can be adjusted appropriately.
4. The transverse contraction joint should be in the form of false joint. When the concrete reaches 25% ~ 30% of the design strength, the joint cutting machine should be used for cutting. The distance between transverse contraction joint and other transverse joints shall not be less than 2m.
5. Half of the length of transverse joint dowel bar should be fixed in concrete, and the other half should be asphalt, allowing sliding. The dowel bar is perpendicular to the seam wall and parallel to the center line, and should be installed with the supporting body.
6. When the tunnel is in a bad geological section, settlement joints should be set at a certain distance from the lining in the tunnel. Transverse construction joints, contraction joints and expansion joints of cement concrete pavement should be combined with settlement joints of lining in the tunnel.
7. Sand and gravel sundries should be removed before caulking, and caulking materials should be injected in time after the curing period expires. The sealing injection depth should be 3 ~ 4 cm, and the sealing material should be flush with the height of the panel in summer construction, and slightly lower than the height of the cement concrete panel in winter construction. Joint sealant with strong adhesion and good elasticity should be selected.
8. Special tools must be used for road surface roughening and grooving, and they should be done well before the cement slurry hardens. It is forbidden to use cement slurry to peel off the road surface when napping, and cement slag shall not be formed.
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