5.对于大体积的混凝土工程，缺少两次抹面，产生表面收缩裂缝。6.大体积

5. For large volume of concrete construction, two missing plaster, generation of surface shrinkage cracks. <br><br>6. A large volume of concrete poured allowed calculation of hydration, insulation work site in place of concrete and cool, causing the internal temperature of the concrete is too high or too large temperature difference between the inner and outer concrete crack generation temperature. <br><br>7. site conservation measures in place, concrete early dehydration caused by shrinkage cracks.

5. For large-volume concrete works, the lack of two surfaces, resulting in surface shrinkage cracks.<br><br>6. Large volume concrete pouring in the hydraization calculation is not allowed, insulation work is not in place and the site concrete cooling, causing the internal temperature of the concrete is too high or the internal and external temperature difference is too large to cause the concrete temperature cracks.<br><br>7. On-site maintenance measures are not in place, the concrete is dehydrated early, causing shrinkage cracks.

5. For large volume concrete works, there is no twice plastering, resulting in surface shrinkage cracks.<br>6. In the process of mass concrete pouring, the calculation of hydration is not accurate, the insulation work is not in place and the concrete on site is cooled down, which leads to the high internal temperature of concrete or the excessive internal and external temperature difference, resulting in the temperature crack of concrete.<br>7. The on-site maintenance measures are not in place, and the concrete is dehydrated early, causing shrinkage cracks.<br>