EN 846-6-2012 pdf download.Methods of test for ancillary components for masonry – Part 6:Determination of tensile and compressive load capacity and load displacement characteristics of wall ties (single end test).
NOTE Clamping fadures wiH invalidate the deformation measurement and therefore specially designed clamps may be needed for particular tie forms. The use of low melting pont alloys to act as chucks is recommended for complex pressing. Some frame ties will require special clamps to de& with the nailing/screwing
5.3 A test machine capable of applying the load without distortion such that the maximum load reading occurs above 20 % of the full scale reading.
The load shall be measured using a load cell device having a digital or analogue readout with a maximum error of 2 % of the full scale reading. The system shall apply an axial force to the specimen. The system or universal test machine shall be fitted with a ngid connection between the damp which is used to apply tension or compression loads and the machine cross-head or loading device, i.e. any pivot ball joint or universal joint connections to the load cells shall be locked.
5.4 A means of measuring the displacement of the specimen in relation to the clamp using at least two symmetrically placed dial gauges or electrical linear displacement transducers (as shown in Figure 1),
Displacement shall be measured to the nearest 0.01 mm.
5.5 For polymer-based (plastic) products only, a controlled temperature and humidity
chamber or room which may be a chamber which fits over the specimen.
6 Preparation and storage of test specimens
6.1 General
Ten specimens each for compression and tensile testing shall be prepared for testing at the declared minimum embedment length. The number of specimens for each shall be doubled where both ends of asymmetrical ties are tested separately.
NOTE The fastening or tie should be installed approximately perpendicular to the lace of the supporting material. Where the design of the tie precludes this, the manufacture?s fixing instructions should be followed,
6.2 Timber frame
Cut or manufacture timber frame squares consisting of a piece of sheathing material fixed centrally to a length of stud by sheathing nails at 150 mm centres. None of the nails shall be closer to the centre of the stud than 20 mm. Fix ties to these timber frame squares using the fastenings provided with the ties and following the tie manufacturers instructions. Ties shall be located to within ± 10 mm of the centre of the timber frame square. (A typical specimen is shown in Figure 3.)
Install lengths of the slot section flush against one face of a wall mould of suitable dimensions using nails or proprietary dips. The slot should be a minimum of 150 mm from any edge of the wall and from any adjacent slot section. Fill the whole slot section with foam plastic or use some other reliable technique to exclude concrete and laitance during setting. The wall should be a minimum of 100 mm thick. Fill the mould with concrete complying with the specifications given in 4.7 using vibration to ensure good compaction. (Figure 4 shows a typical slot wall specimen.)
6.5 Masonry units
Use either whole or part masonry units having at least one dimension of 215 mm or greater. Fix ties to them using the fastenings provided with the ties following the tie manufacturers instructions. Ties shall be located to within ± 10 mm of the centre of the unit. If the units are perforated or hollow, the ties shall be secured in the area of the perforated or hollow section.
6.6 Storage
If fresh concrete or mortar are used take appropriate steps to prevent the test specimen from drying out during the first three days after construction. e.g. by covering it with a polyethylene sheet and then leave it uncovered in a laboratory environment until tested.
7 Procedure
7.1 SettIng specimen In test machine
a) Load the specimen into the test system or test machine such that the tie body axial and aligned at the centre of action of the test machine where no movement tolerance or slope tolerance is specified for the particular tie system; or
b) In the case where slope tolerant or movement tolerant ties are required to be tested, offset one end of the specimen over a distance which gives the maximum slope or half the maximum movement specified by the manufacturer and repeat this in both directions for fifty times; after this, offset one end of the specimen from the centre of action of the test machine or test system by a distance which gives the maximum slope or half the maximum movement specified by the manufacturer.
When testing in tension, the damp may be applied to the tie at a distance from the frame, concrete or masonry equal to the cavity width at which the tie is intended to be used. When testing in compression. the clamp may be applied to the tie at a distance from the frame, concrete or masonry equal to the cavity width at which the tie is intended to be used plus 15 mm. Alternatively where the resistance of the anchorage is to be determined separately from the section which bridges the cavity. the clamp should be placed close to the face of the frame, concrete or masonry. In the case of compression, testing a gap of approximately 5 mm is required. The distance from the damp to the frame, concrete or masonry should be measured and recorded.EN 846-6-2012 pdf download.