بهمن نیرومند

This article deals with study of new method of impact compaction as one of the methods for dynamical compaction of soils in a small scale on-site. Impact compaction system is one of the methods that can be used for dynamic compaction of layers with small to medium thickness and as a substitute for excavation and replacement with engineering embankment. The basis of this method is the impact compaction of soil masses on points located on a network with a triangular or square pattern using a tamper attached to a hydraulic hammer mounted on a mechanical excavator. As a result of using this technology, there is the possibility of compacting layers with low to medium thickness instead of compacting layer by layer for rapid improvement of not hammered soils. In this research, it is used from three separate tampers with a diameter of 12, 16 and 20 cm can be installed on an electric hammer. Distance between the compaction points is considered in both triangular and square patterns of 40 cm. The results show that among these tampers, the tamper with diameter of 16-cm has the best compaction performance in both triangular and square patterns. The effective depth for this tamper per 62 Jules energy per each impact, equal to 50 centimeters or 3 times the diameter of the tamper. Also, the relative density of the subsoil under the tamper up to 1.5 times the diameter of the tamper in the triangular pattern is about 97 percent.