High-Performance Concrete, Really High Performance? - The Issues and Discussion of Modern Concrete Science - page 162

2. W/C

W/C of stiff concrete is 0.38 0.45 usually, semi-stiff concrete is 0.45 0.50, and

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plastic is commonly 0.5 0.6, while W/C of HPC is generally 0.4 0.55 and W/B

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(water to binder ration) is within 0.3 0.4.

W/C of HPC is similar to that of plastic concrete, but the W/B is much smaller
than OPC.

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3. Cement consumption

After taking C50 concrete for example, cement consumption of stiff concrete is
usually 280

330 kg, semi-stiff concrete is usually 330 380 kg, and plastic concrete

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is usually 380 450 kg. However, cement consumption of HPC is commonly

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300 400 kg, and other cementitious material must be added with a content of

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100 250 kg ordinarily.

It is thus clear that although cement consumption of HPC is not high enough,
total amount of cementitious material is considerably larger than OPC.

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4. Sand ratio

Taking C50 concrete for example, sand ratio of stiff concrete is usually
0.28 - 0.32, semi-stiff concrete is usually 0.32 - 0.35, and plastic concrete is usually

0.35 0.40, while sand ratio of HPC is commonly 0.4 0.5,

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So, sand ratio of HPC is much bigger than OPC.

5. Coarse aggregate content

Taking C50 concrete for example, coarse aggregate content of stiff concrete is
usually 1380 1450 kg, semi-stiff concrete is usually 1320 1380 kg, and plastic

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concrete is usually 1100 1300 kg, while coarse aggregate content of HPC is

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commonly 800 1000 kg.

As can be seen, coarse aggregate content of HPC is less tan OPC.

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6. Maximum grain size of coarse aggregate

Maximum grain size of coarse aggregate OPC is 4 cm, and for HPC, it has been
reduced to 2 cm at present.

7. Unit weight

Taking C50 concrete for example, unit weight of stiff concrete is usually
2480 2550 kg, unit weight of semi-stiff concrete is usually 1320 1380 kg, and

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plastic concrete is usually 2250 2330 kg, while unit weight of HPC is commonly

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2300 2400 kg.

It is clear that unit weight of HPC is similar to that of plastic concrete, but lower
than that of stiff and semi-stiff concrete in OPC.

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8. Water reducing agent
High-range water-reducing agent is usually employed in HPC; its water-reducing
rate is much higher than water-reducing agent used in OPC.