Cube Moulds

Cube Moulds

The standard size of cube is 150 mm.

Cubes of 100 mm size are not suitable for concrete having a nominal maximum aggregate size exceeding 20 mm.

Cubes of 150 mm size are not suitable for concrete having a nominal maximum aggregate size exceeding 40 mm.

 The moulds for the specimens must be made of cast iron or cast steel. The inside faces must be machined plane. The cube mould is normally made in two halves to facilitate removal of the concrete cube without damage. Each mould has a base, which is a separate metal plate, preferably fastened to the mould by clamps or springs. When assembled, all the internal angles of the mould must be right angles.

To comply with CS 1:1990, moulds are required to be within specified tolerances for dimensions, squareness and parallelism. These are covered in Section 7 of CS 1.

 Preparing the Moulds

Before assembling the moulds, make sure that there is no hardened mortar or dirt on the faces of the flange that prevent the sections from fitting together closely.

These faces must be thinly coated with mould oil to prevent leakage during filling, and a similar oil film should beprovided between the contact surfaces of the bottom of the mould and the base. The inside of the mould must also be oiled to prevent the concrete from sticking to it. The two sections must be bolted firmly together, and the moulds held down firmly on the base plates.