Yahya Ghasemi Print III pdf

4.1.4. Packing methods
The methods of packing can be classified based on the compaction energy used in the process 
of packing. According to European standard EN-1097:3, loose packing can be achieved by 
pouring the aggregates in a standard cylinder from the distance of maximum 50 mm.
American standard ASTM C29 deals with the process of measuring hard packing in which the 
container is filled to one third of its volume, then the layer of material is compacted using 
rodding with 25 strokes and the process continues with filling the next one third of the volume 
and rodding as the same manner as the first layer and then the procedure continues for the 
third layer.
Another procedure for packing the particles is suggested by De Larrard (1999), in vibration + 
compaction method, the aggregates will be poured in a cylinder that is closed with a 20 kg 
steel piston and the whole setting will be put on a vibration table and shaken by following 
vibration sequences: 2 min,40 s and 1 min at amplitudes 0.4 mm, 0.2 mm and 0.08 mm 
respectively.Obviously, the choice of packing method affects the packing density measured 
on the same aggregates (Johansson and Emborg, 2014). 
The selection of the packing method has an obvious effect on the packing density. However, 
among the discussed particle packing models, CPM is the only models that considers the 
effect of packing method by means of compaction index 
K
(see Section 3.2.3 and Figure 3.2.) 
which is an empirical value that can be calibrated based on the method of packing. For 4C 
model, the manual suggests using hard packing while Toufar model does not mention a 
specific packing method. In the study conducted in Paper II, all of the packing density values 
were obtained based on loose packing since the method is less energy and time consuming. 
Moreover, loose packing data was chosen as input in all of the models so they can be treated 
in the same way which makes the comparison of the models more sensible.