Impact compaction action
SUPPLY CHAIN NEWS
Anro Impact Compaction
An Anro impact compactor towed by a Bell 2806 hauler.
Impact compaction action
Anro Impact Compaction recently sold Fraser Alexander two five-sided impact compactors for use on their Elikhulu site, where they are constructing a large tailings storage facility. The project involves constructing a tailings dam with large earth-filled walls, two smaller HDPE-lined water dams, as well as various other civil works. The impact compactors are being used to compact the imported fill material on the dam walls. The impact compactors were necessary because the project is being constructed over a brief period and has strict milestone dates that must be achieved. To do so, Fraser Alexander needs to compact in excess of 18 000m 3 of compacted fill every day, with the material for the dam walls coming from borrow pits inside the dam. Contracts manager Johannes Vorster says:“ The impact compactors work great where you have thick layers of even up to a metre to compact. We are filling in 300mm layers due to the very stringent compaction specification required by the design engineer. Our reason for using Anro impact compactors on this site is that we can compact twice the amount of earth per day than we could using normal 10-ton rollers.” Roger Stromsoe of Anro Impact Compaction says they manufacture two types of impact compactors: a five-sided and a three-sided compactor. They are rated according to their energy output; the five-sided being a 15kJ compactor
and the three-sided a 30kJ compactor. The five-sided impact compactor is a more general-purpose compactor, mainly used on earthworks where use of this impact compactor makes it possible to place material in thick layers. Depending on the material type, fill can be placed in layers of 500 – 700mm thick and more. This gives the compactor an output of about 2 000m 3 per hour compared to the output of a vibro roller of about 300m 3 per hour on the same material. The five-sided compactor is also used on in situ material on sites where only moderately deep compaction is required. The 30kJ, three-sided impact compactor is generally used for the compaction of in situ material on sites where deep compaction is required. Because the depth of influence of an impact compactor is significantly greater than that of conventional equipment, use of the three-sided compactor usually makes it possible to satisfactorily compact soil from the surface, instead of having to remove the soil and replace it in layers, as would be the case with vibro rollers. Depending on the material type, in situ material can be improved to depths of up to three metres. On many construction sites, the impact compactor has been the only compactor that could achieve the required densities by compacting the site surface without having to remove and replace the material in layers, resulting in significant cost saving. The three-sided compactor is also used on fill where there is an advantage in placing very thick layers.
40- CEC August 2018