BS EN 13286-52:2004 – Unbound and hydraulically bound mixtures — Part 52: Method for the manufacture of test specimens of hydraulically bound mixtures using vibrocompression

1 Scope
This document specifies a test method for making specimens of hydraulically bound mixture to a predetermined density and water content by vibrocompression compaction.
This document is appropriate to mixtures, or that part of a mixture, containing aggregate up to a maximum size of 31 ,5 mm.
This method is not applicable to mixtures with a high proportion of fines.
2 Terms and definitions
For the purposes of this document, the following term and definition applies.
2.1
vibrocompression compaction
method of compaction of a laboratory specimen by the simultaneous application of horizontal vibration and light axial compression
3 Principle
The mixture is placed in a mould of a given volume. The mixture is compacted with a combination of horizontal vibration and vertical axial pressure.
4 Dimensions of the specimens
4.1 Cylindrical specimens
Specimens shall conform to the dimensions given in Table 1 .
4.2 Direct tensile test specimens
Specimens for direct tensile test shall have the shape and dimensions in millimetres shown in Figure 1 .
5 Apparatus
5.1 Moulds
5.1.1 Moulds, made from rigid materials, e.g. plastic or similar, with a volume accuracy of ± 1 ,5 % of the nominal volume of the specimen.
5.1.2 Moulds shall be tubes to which caps can be attached to cover each end of the specimens after compaction in order to prevent loss of moisture during storage.
5.1.3 Moulds for cylindrical specimens (see Figure 2) shall be cut on one generatrix to allow slight opening of the mould in order to remove the specimen after setting.
5.1.4 Moulds for direct tensile testing shall be capable of producing cylindrical specimens with a cross section shown in Figure 1 and shall be split on two opposite generatrix in order to remove the specimen after setting.
5.2 Compaction apparatus (see Figure 2)
5.2.1 Cylinder, to stiffen the mould and lengthen the top end of the mould to allow introduction of the mixture before compaction.
5.2.2 Plate, to close the bottom of the mould.
5.2.3 Vibrator, to apply a horizontal vibration to the mould and the mixture with a frequency of 1 00 Hz and an amplitude between 0,8 mm and 1 mm. The vibration shall be sufficient to compact the specimen to the required density within 90 s using a pressure on the mixture not greater than 0,5 MPa.
5.2.4 Piston, to apply an increasing vertical pulse pressure on the mixture during compaction.
BS EN 13286-52:2004 – Unbound and hydraulically bound mixtures — Part 52: Method for the manufacture of test specimens of hydraulically bound mixtures using vibrocompression