Silt content (%)

Concrete strength grade

≥C60

≤0.5

0.4

C55~C30 or concrete featured with anti-freezing, anti-permeability or   other special requirements

≤1.0

≤C25

≤2.0

Clay lump content (%)

Concrete strength grade

≥C60

≤0.2

0.1

C55~C30 or concrete ﹤C30 and featured with   anti-freezing, anti-permeability or other special requirements

≤0.5

≤C25

≤0.7

Total content of acicular, flaky particles (%)

Concrete strength grade

≥C60

≤8

3

C55~C30

≤15

≤C25

≤25

Crushing value index (%)

Type of rock

Concrete strength grade

Crushing value index

7.7

Crushed rock

Sedimentary rock

C60~C40

≤10

≤C35

≤16

Metamorphic rock or plutonic igneous rock

C60~C40

≤12

≤C35

≤20

Extrusive igneous rock

C60~C40

≤13

≤C35

≤30

Pebble

C60~C40

≤12

≤C35

≤16

Organic content

The color shall not darker than the standard. If it do, the substance   should be process as concrete for strength contrast test with a compressive   strength ratio not smaller than 0.95.

Qualified

Rigidity

Mass loss rate (%)

Applicable to concrete used outside at severe cold or cold areas or   usually at a wet state or an alternate wetting or drying state; concrete with   corrosive medium function or usually at areas of water level change under the   ground or with requirements for anti-fatigue, wear-resistance or   shock-resistance.

≤8

2

Applicable to concrete used for other conditions.

≤12

Rock strength (MPa)

Should be at least 20% higher than processed concrete in strength.

130

Content of sulfide and sulfate (%)

≤1.0

0.12

Apparent density (kg/m³)

--

2670

Bulk density (kg/m³)

--

1520

Tight density (kg/m³)

--

1580

Porosity (%)

Loose

--

43

Tight

--

41

Water absorption (%)

--

0.86

Moisture content (%)

--

0.9

Chloridion (%)

--

0.001

Alkali content (%)

--

5.12

Radioactivity

Internal exposure index I_ra

≤1.0

0.3

External exposure index I_r

≤1.0

0.5

Grain Composition

Nominal size (mm)

80

63

50

40

31.5

25.0

20.0

16.0

10.0

5.00

2.50

(5~20) mm grain composition range accumulated screening (%)

-

-

-

-

-

0

0~10

-

40~80

90~100

95~100

Actual accumulated screening (%)

/

/

/

/

/

0

4

26

66

94

99

Screening conclusion

The grain composition of the sample is in conformity with (5~20) mm   continuous composition range.

Remarks

/