How many pounds of pressure do you need for tamping? - HENGDA RIC

Apply 20-30 pounds of pressure, and polish Baristas often recommend 30 pounds of pressure, but some do as little as 20 pounds. More and more are finding that tamping pressure is overrated—it's hard on the wrist and cause an over-extracted, bitter brew. Use a twisting motion as you pull up to “polish” the puck.

The Rapid Impact Compaction technology works very well for all kinds of non-cohesive soils, especially for the compaction of gravels and sands. It can also be used on reclaimed areas where anthropogenic soils and uncompacted fills occur.

Most often, the RIC technology is used for the construction of enclosed buildings: under the foundation slabs/floors of industrial and commercial halls and under heavy surfaces of warehouses, tanks; for the construction of infrastructure: all types of roads and highways, under the road and rail embankments and often as the improvement of the base for parking lots and airport runways. A great advantage of the RIC method is its mobility and relatively small size of the equipment unit which allows for carrying out the works in areas with difficult access.

Depending on the soil type, water conditions and parameters of the hammer the soil compaction range reaches a depth between 4.0 and 5.0 m.

A safe working distance from the existing buildings, for which vibration monitoring is not necessary, amounts to approximately 5.0 up to 6.0 m. Than, the generated noise is within 90 dBA.

RIC technique is performed at the surface of a terrain and it comprises of a heavy excavator which is equipped with a specially designed arm onto which the hammer is attached. Within the hammer, a 5 to 10 drop weight is hydraulically lifted till a required height after which the weight is dropped using a hydraulic acceleration. This whole process of lifting and dropping of the weight takes place with a frequency of 30 to 80 times a minute.

Rapid Impact Compaction (RIC) is an innovative dynamic compaction device mainly used to compact sandy soils, where silt and clay contents are low. RIC closes the gap between the surface compaction methods (e.g. roller compaction) and the deep compaction methods (e.g. deep dynamic compaction) and permitting a middle-deep improvement of the ground. RIC has been used to treat a range of fills of a generally granular nature and some natural sandy and silty soils.

RIC can be used to improve bearing capacity and reduce liquefaction potential of loose soils. The compaction sequence is designed to work from the outside in, so that compaction of the lower zone soils occurs first followed by compaction of the upper zone. Data monitoring during the compaction process and the online display in the operator’s cab enables compaction control, an economic application of the compaction tool, and a work integrated quality control. The total impact depth of the impact foot, the number of blows, and the final settlement of the impact foot after a blow define the stopping criteria.