Dear reader we have discussed about straight forward limits for fineness of sand used in concrete according to different standards of the world. Here we like to explain some additional requirements except fineness.
Dear reader we have learnt about limits of fineness modulus according to AASTHO and ASTM. These values were between (2.3-3.1). But if aggregate do not meet these requirements what should be done? Should it be considered as unusable? We will find this answer in next paragraph.
The fine aggregate that don’t meet this requirements can be used if we have some data about the concrete produced with this aggregate can be accepted of –
Concrete produced with identical fine aggregate collected from same source, produce acceptable performance in identical concrete construction.
Concrete of the type specified, produced with desired fine aggregates, should posses relevant properties (that properties, important for particular application, we considered) at least become equal to that of concrete having same constituents, having exception that fine aggregate that is referenced should be collected form source that have acceptable performance report identical concrete construction.
We have discussed about fineness modulus above but other requirements that have to meet are:
1. Less than or equal to 45% of fine aggregate should not pass through any standard sieve.
2. Similar equal percentage of fines should not retain on two consecutive sieves.