Loose Cement -Rejection procedure or Validity ?(Stock at Cement silo)

Krishna22

Apprentice
As per IS-455:1989 clause-12-Rejection mention-6 month at silo or bulk storage but after 6 month Re-test will be conducted if result is ok as per IS but decreasing result.
like- Fresh Cement (33 grade-PSC)-44 MPA
after Six Month (33 grade-PSC)-35 MPA

We can used in structure ? i think Design Mix concrete result will be affected . Only used in finishing work like,brick work,plaster etc.
 

Dnyan Deshmukh

Staff member
Loose cement in stored in the silos are safe to consume up to period of the 6 moths as there is no much environmental impact on it.
Cement starts to loose its properties when it comes into contact with water or moisture from air, till the time reaction is not started, cement does not loose its properties.

It is difficult to state either the whole cement lot or part of it, got infected due to coming into contact with H2O. using the cement post 6 months from the manufacturing involves the high risk factors and even testing of cement involves further more period before actual consumption of it.

It is always better, not to use cement older than 6 months into a structural concrete, you can safely consume the cement in non-structural activities (finishing works) as there is not requirement of high strength like concrete.
 
  • Like
Reactions: Mehboob

Mehboob

Senior Member
As per IS-455:1989 clause-12-Rejection mention-6 month at silo or bulk storage but after 6 month Re-test will be conducted if result is ok as per IS but decreasing result.
like- Fresh Cement (33 grade-PSC)-44 MPA
after Six Month (33 grade-PSC)-35 MPA

We can used in structure ? i think Design Mix concrete result will be affected . Only used in finishing work like,brick work,plaster etc.
We cannot use in structural members as it increases maintenance costs in future, better to use after retest if it satisfies strength parameters.yes we can use in non structural members like plastering,slurry for pumping concrete etc