Cube test of concrete as per is code


Cube test of concrete as per is code



Pouring of empty cube mold for compressive strength of concrete as per pressured follows  by IS code 516

M25 =28.3 N/mm2

M30=34.13N/mm2

M40=44.125 N/mm2

M45=49.125 N/mm2

Size cube

1. 150 X 150 X 150

2. 100 X 100 X 100

Procedure of filing mold

3 step pouring after one step 16mm tempering rod 35 stock .generally used size as site 150 X 150 X150 .after 20 hrs removed mold curing 7 days.

Sample taken

0 to 5 cum one set

6 to 15 cum two set

16 to 30 cum three set 

31 to 50 cum four set 

Every 50 cum one set sample taken .one set is 3 number .

If when we are testing one set cube for 7 days and one set cube for 28 days .

Target strength of concrete

For 28 days 

Strength =fck +0.825× standard dilation

For M30 standard deviation is 5

For 7 days 

60 percentage of our 28 days target strength 

SI Code  

1. 456:2000 for testing of concrete

2. 516 for poring of concrete

Test specimen 

Three test specimen shall be made for each sample for testing at 28 days .addition sample may be required for various purpose such as determine the strength concrete at 7days or at the time of striking the formwork or to determine the duration or curing to the testing error additional sample may also be required for testing sample cured by accelerated method as described in IS 9103.

Test Result of Sample 

The test result of sample shall be average of the strength of three specimen individual should not be more than +-15 percent of the average . 

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