ST’s mixes are a defined list of concretes within National Annex:2015+AC1:2017 to I.S. EN 206:2013 which are made with a prescribed quantity of materials as required in the European Standards. These concretes are normally mixed on site or obtained from not a third party accredited ready mix suppliers.
A wide range of application depending on category. From non-structural concrete such as blinding (ST1, ST2) to structural applications like foundation or slabs (ST3, ST4).
STs are basic mixes and have no strength guarantee, although this can be assumed based on the values contained within National Annex:2015+AC1:2017 to I.S. EN 206:2013. The equivalent design mixes may be used as alternatives to the corresponding ST mix designation.
Alternative equivalent design mixes as per Table NB.2
Standard prescribed mix
Alternative equivalent mix if supplied form a third party accredited ready mix supplier N/mm2