The use of concrete for construction provides some great advantages, such as ease of use and strength. When concrete is in it’s liquid form it is very easy to use, but when it dries it provides incredible strength that will last for years. Despite the fact that concrete is a great source of construction material for everything from concrete floors, to building foundations, bridges and tunnels, there could be some problems concrete san francisco with the concrete over time. Some issues that may arise include the overall strength of the concrete itself, as well as corrosion due to the concrete being exposed to excessive moisture; in addition, the surrounding soil composition could also cause some problems. Not only could low quality materials and improperly mixed concrete be costly later, but it can also be dangerous if the result diminishes the concrete’s strength. To avoid these problems it is advisable to always use high quality concrete and to stay vigilant for possible problems with the concrete.Some of the most common concrete problems include,
Dusting: The surface of the concrete will form a loose powder, which indicates that the surface of the concrete is disintegrating. This can be caused by water bleeding into the concrete during finishing. This may cause the concrete to have a high water ratio, leading to a weakened surface. Additional causes of this concrete problem may include using heaters during a cold weather operation without adequate ventilation, which may cause excessive carbon dioxide, leading to carbonization, or allowing the surface of the concrete to freeze.
- Flaking & Peeling: The freezing and thawing process of finished concrete often causes flaking and peeling; some of the factors that may contribute to this problem include, not using air-entrained concrete, which is a must to protect the concrete from the affects of freezing and thawing. In addition, if there was too much calcium chloride used as an accelerator, this may also cause a problem with peeling and flaking. Some other situations that may cause concrete to flake and peel include working the surface of the concrete too much, insufficient curing, water bleed, or using deicer.
- Fine Cracks in the Surface of the Concrete: In some cases the surface layer of concrete may begin to form a network of fine cracks. This problem is often caused when a rapid drying procedure was used, or there was inadequate curing of the concrete. Other contributing factors may include water on the surface during finishing, or the sprinkling of cement on the surface in order to dry the water bleed.
- Cracking: The most common reason that concrete cracks is due to the expansion and contraction of the concrete without s sufficient means of relieving stress. This could be the result of improper jointing, shrinkage, and settlement. Other contributors to this problem include freezing and thawing, or external restraint, such as flooring.
- Shrinkage: Another common problem with concrete is cracking due to shrinkage. This may occur when there is a rapid evaporation of the surface before the concrete has set.
- Reduced Strength of Concrete: This can happen when improper casting, handling and curing procedures are used; additional causes may include high air content, too much water, or an error in the manufacturing of the concrete.
- Delamination: This is a situation where there is a separation between the top slab and bottom slab that may be caused by a thin layer of water or air. Some situations that may lead to this problem include when air entrained concrete is used for hard finishes, sealing the surface while there is still bleed water present, overworking the surface, or using a polyethylene vapor barrier.
- Discoloration: Some of the most common causes of concrete discoloration include using calcium chloride to speed set times, changes in the mix proportions or material sources, uneven curing.
- Curling: When curling occurs, essentially what happens is that there is a distortion of the flat surface into a curved shape. This is frequently the result of a difference in the temperature of the moisture content between the top and bottom of the slab.
- Uneven or Spotty Setting of Concrete: The most common cause of this problem is not mixing the concrete thoroughly, and the use of some superplasticizers with normal setting or retarding admixtures.
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