1514Benefits to Construction

Many advantages have been brought to construction with the application of HPC. The following highlights the primary construction-related benefits:

1. High strength. HPC, generally speaking, has high compressive strength. The high-strength property, on the one hand, can increase the load carrying capacity of the structural members such as steel bar reinforced concrete columns and shells, resulting in less reinforcing steel and labor consumption, and materials costs saving. On the other hand, by keeping the same load, the cross-section size of the primary structural members can be considerably diminished. The benefit to flexural strength of construction components can also be improved due to high strength. Although high strength cannot enhance the flexural strength too much, the compressed region depth can be greatly decreased for the bended members and the corresponding ductility is markedly improved. Meanwhile, higher steel bar ratio can be allowed for, which further increases the flexural strength or reduces the cross-section size.

2. Improved workability. Due to the addition of water reducing admixtures, especially super-plasticizer, and the increased cement content in HPC, the workability of HPC, including fluidity and cohesiveness, is generally improved. For self-compacting concrete, a type of HPC, the concrete can flow in mold without compaction.

3. Low volume change. The lower volume deformation of HPC brings about an increase in stiffness, which is very beneficial to those beams and plates whose cross-section sizes are controlled by deformation. As with prestressed enforcement concrete members, three advances can be obtained: higher prestress gain, earlier applied prestress, and less loss in prestress.

4. HPC has a special significance for these constructions whose loads primarily come from the self-weight. There can be a great improvement in reducing the bearing load of foundations by using HPC. Furthermore, more space can be effectively utilized for housing constructions caused by the smaller cross-section size using HPC. For bridge constructions, more net space below the bridge decks and the lower roadbed can be obtained. For underground engineering, the use of HPC may reduce the excavation mass. In addition, the construction modules can be adjusted into identical sizes, resulting in a lower production cost of modules.

5. Enhanced dwrabiiifies. Greatly enhanced durability properties of HPC allow the overall life of the structure to be significantly extended. The period of time until maintenance is needed is much longer than conventional concrete, therefore, there is less disruption to the public due to repairs and less maintenance costs. In addition, HPC is less permeable than conventional concrete, which makes it more resistant to salts in seawater, freeze-thaw cycles, and damage caused by chemical deicing, which is very attractive in environments where ordinary concrete would not suffice such as marine, high rate running water, or easily collision engineering.

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