Advantages of Lightweight Concrete
Following are the advantages of lightweight concrete:
- The local industrial waste, if found suitable for lightweight concrete, can be economically utilized.
- The reduction in weight of concrete helps easy removal, transport and erection of precast products.
- The use of lightweight concrete results in the reduction of cost to the extent of about 30 to 40 percent.
- The lightweight concrete doesn’t present special problems with respect to freezing and thawing. It is due to the fact that the larger pores in aggregate are unlikely to become saturated, provided the cement paste is protected by air entrainment.
- The lightweight concrete has comparatively less tendency to spall. Hence, its fire resistance is greater as compared to the ordinary concrete.
- The lightweight concrete has generally a lower thermal expansion than ordinary concrete.
- The sound absorption of lightweight concrete is good because of the fact that the air-borne sound energy is converted into heat in the minute channels of the concrete. The sound absorption coefficient of the lightweight concrete is nearly twice than that of the ordinary concrete.
Disadvantages of Lightweight Concrete
The only drawback of lightweight concrete is that the depth of carbonation i.e. the depth within which corrosion can occur under suitable conditions is nearly twice than that of normal concrete. Hence, special care will have to be taken to provide sufficient cover to the reinforcement of the lightweight structures to grant protection against corrosion.