MSC 85/26/Add.2 ANNEX 3 RESOLUTION MSC.268(85) - US Coast ...

MSC 85/26/Add.2ANNEX 3Page 332Consequently, it is recommended that a preliminary flow moisture test should be conducted,generally in accordance with the following, to indicate the condition of the test sample, i.e. thequantity of water and the rate at which it is to be added or whether the sample should be air-driedto reduce its moisture content before commencing the main flow moisture test.1.1.4.1 Preparation of the test sampleThe representative sample of test material is placed in the mixing bowl and thoroughly mixed.Three subsamples (A), (B) and (C) are removed from the mixing bowl as follows: about one fifthof the sample (A) should be immediately weighed and placed in the drying oven to determine themoisture content of the sample “as received”. Two further subsamples, each of about two fifthsof the gross weight, should then be taken, one (B) for the preliminary FMP test and the other (C)for the main FMP determination:.1 Filling the mould. The mould is placed on the centre of the flow table and filledin three stages with the material from the mixing bowl. The first charge, aftertamping, should aim to fill the mould to approximately one third of its depth.The quantity of sample required to achieve this will vary from one material toanother, but can readily be established after some experience has been gained ofthe packing characteristics of the material being tested.I:\MSC\85\26-Add-2.docThe second charge, after tamping, should fill the mould to about two thirds of itsdepth and the third and final charge, after tamping, should reach to just below thetop of the mould (see figure 1.1.4.2)..2 Tamping procedure. The aim of tamping is to attain a degree of compactionsimilar to that prevailing at the bottom of a shipboard cargo of the material beingtested. The correct pressure to be applied is calculated from:Tamping pressure (Pa) = Bulk density of cargo (kg/m 3 )x Maximum depth of cargo (m)x Gravity acceleration (m/s 2 )Bulk density can be measured by a single test, using the Proctor C apparatusdescribed in ASTM Standard D-698 or JIS-A-1210, on a sample of the cargo atthe proposed moisture content of loading.When calculating the tamping pressure, if no information concerning cargo depthis available the maximum likely depth should be used.Alternatively, the pressure may be estimated from table 1.1.4.1.The number of tamping actions (applying the correct, steady pressure each time)should be about 35 for the bottom layer, 25 for the middle and 20 for the top layer,tamping successively over the area completely to the edges of the sample toachieve a uniformly flat surface for each layer..3 Removal of the mould. The mould is tapped on its side until it becomes loose,leaving the sample in the shape of a truncated cone on the table.