SUB-BASE MATERIALS

Sand Masters is a leading supplier of sub-base materials to the civil and construction industry within and around Gauteng. Specifically designed to provide supporting structures in any pavement and road design, our sub-base material specifications comply with COLTO specifications and are tested by accredited laboratories.


G1 & G2

Crushed Stone

G1 Sub-Base Material is primarily used in road construction. In order to achieve the required degree of particle interlock, the material for G1 has to be crushed from un-weathered rock and no material other than from the parent rock may be used or added to correct the grading. The fines added may not have an LL exceeding 25 and a PI not exceeding 4. The nominal maximum size is 37.5mm

G2 Sub-Base Material may contain up to 10% by mass of approved natural fines not necessarily obtained from the parent rock. Added fines may not have a LL exceeding 25 and a PI exceeding 6. The nominal maximum size is 37.5mm


G4 & G5

Crushed Stones

G4 Sub-Base Material is used as filling and a base coarse under roads and paving. This material may contain approved additional fines not obtained from parent rock. Added fines shall have a liquid limit not exceeding 25 and a plasticity index not exceeding 6. The nominal maximum size for uncrushed material is 53mm and for crushed 37.5 or 26.5mm.

G5 Sub-Base Material is used as filling and a base coarse under roads and paving. This material may contain approved natural fines not obtained from parent rock. The nominal maximum size for uncrushed material is 63mm and for crushed 53mm.


G6 & G7

Crushed Stone sub base material

G6 Sub-Base Material is used as filling and a base coarse under roads and paving. This material may contain approved natural fines not obtained from parent rock. The nominal maximum size for uncrushed material is 2/3 of the compacted layer and for crushed material 63mm before compaction.

G7 Sub-Base Material is used as filling and a base coarse under roads and paving. This material may contain approved natural fines not obtained from parent rock. The nominal maximum size for uncrushed material is 2/3 of the compacted layer and for crushed material 74mm.


G9 & UNSELECTED FILLING

excavator crushing stone

G9 Sub-Base Material and Unselected Filling is used as filling and a base coarse under roads and paving. It a natural material such as soil, gravel and sand. The nominal maximum size for this material is 2/3 of the compacted layer.