Concrete strength

General, C10, C15, C20, C25, C30, how much concrete mix is

The strength of concrete, strength class, different amounts

Concrete strength is divided into a number of grades, concrete strength class is divided by the cube compressive strength of standard FCU,k. The cube compressive strength value is a value in the overall distribution of compressive strength of cubic, strength is lower than the percentage worth no more than 5%, that is 95% of the guaranteed rate. The strength of concrete is divided into C7.5, C10, C15, C20, C25, C30, C35, C40, C45, C50, C55, C60, 12 grades.

Concrete mix proportion refers to the constituent materials in concrete (cement, water, sand, stone) between proportions. There are two ways: one is to 1 cubic metres of concrete in a variety of materials, such as cement 300 kilograms, water 180 kilograms, 690 kilograms sand stone 1260 kilograms; another is a unit mass of cement and the ratio of the amount of material and the water/cement ratio of the concrete to say, for example, the previous example can be written as: C:S:G=1:2.3:4.2,W/C=0.6.

Common level

C20

Water: 175kg cement: sand 343kg: 621kg stone: 1261kg

Mixing ratio: 0.51:1:1.81:3.68

C25

Water: 175kg cement: sand 398kg: 566kg stone: 1261kg

Mixing ratio: 0.44:1:1.42:3.17

C30

Water: 175kg cement: sand 461kg: 512kg stone: 1252kg

Mixing ratio: 0.38:1:1.11:2.72

Ordinary concrete mixture ratio:

Cement

Concrete mix (units) Kng slump mm compression N/mm2

Sand cement water 7 days 28 days

P.C32.5 C20 300 734 1236 195 35 21.0 29.0

1 2.45 4.12 0.65

C25 320 768 1153 208 45 19.6 32.1

1 2.40 3.60 0.65

C30 370 721 1127 207 45 29.5 35.2

1 1.95 3.05 0.56

C35 430 642 1094 172 44 32.8 44.1

1 1.49 2.54 0.40

C40 480 572 1111 202 50 34.6 50.7

1 1.19 2.31 0.42

P.O 32.5 C20 295 707 1203 195 30 20.2 29.1

1 2.40 4.08 0.66

C25 316 719 1173 192 50 22.1 32.4

1 2.28 3.71 0.61

C30 366 665 1182 187 50 27.9 37.6

1 1.82 3.23 0.51

C35 429 637 1184 200 60 30.***6.2

1 1.48 2.76 0.47

C40 478 *** 1128 210 60 29.4 51.0

1 1.33 2.36 0.44

P.O 32.5R C25 321 749 1173 193 50 26.6 39.1

1 2.33 3.65 0.60

C30 360 725 1134 198 60 29.4 44.3

1 2.01 3.15 0.55

C35 431 643 1096 190 50 39.0 51.3

1 1.49 2.54 0.44

C40 480 572 1111 202 40 39.3 51.0

1 1.19 2.31 0.42

P.O

42.5(R) C30 352 676 1202 190 55 29.***5.2

1 1.92 3.41 0.54

C35 386 643 1194 197 50 34.5 49.5

1 1.67 3.09 0.51

C40 398 649 1155 199 55 39.5 55.3

1 1.63 2.90 0.50

C50 496 606 1297 223 45 38.4 55.9

1 1.22 2.61 0.45

PII 42.5R C30 348 652 1212 188 50 31.***6.0

1 1.87 3.48 0.54

C35 380 639 1187 194 50 35.0 50.5

1 1.68 3.12 0.51

C40 398 649 1155 199 55 39.5 55.3

1 1.63 2.90 0.50

C45 462 618 1147 203 4***2.7 59.1

1 1.34 2.48 0.44

C50 480 633 1115 192 25 45.7 62.8

1 1.32 2.32 0.40

P.O 52.5R C40 392 645 1197 196 53 40.2 55.8

1 1.64 3.05 0.50

C45 456 622 1156 19***2 43.5 59.5

1 1.36 2.53 0.43

C50 468 626 1162 192 30 45.2 61.6

1 1.33 2.47 0.41

This test data as a standard laboratory, sand using sand, fineness modulus of 2.94, gravel for the 5~31.5mm consecutive fractions. Each grade of concrete ratio can also be adjusted by adding additives.