What is the depth of rapid impact compaction?

Rapid impact compactor is a kind of pavement compaction equipment, which is mainly used for the back of abutment, culvert side, around pier, slope, turning area of compaction machine to machine, no road area, etc. it can better solve the common problems such as early rise damage of roads after partial subsidence of important facilities such as expressway, bridge abutment jumping, pier inclination, slope sliding, etc. The influence depth of rapid impact compactor is generally about 1~10m. According to the R & D and production technology of each manufacturer, the influence depth will also be affected.

The working principle of the rapid impact compactor is similar to that of the dynamic tamper. The difference is that after the rapid impact compactor is lifted to a certain height, its unique design also provides additional auxiliary thrust under the action of gravity. Under the joint action of the two forces, it falls rapidly, producing a strong impact force, and can obtain a more uniform compactness in a large depth range.

At the same time, the cross-sectional area of the rapid impact compactor is significantly smaller than that of the dynamic tamper. Therefore, the rapid impact compactor has large tamping capacity and deep action. The experimental data show that the effective impact depth of the rapid impact compactor is 1~3m, and the impact depth is 4~10m, which is slightly inferior to the dynamic tamper. Therefore, some people call it "hydraulic dynamic tamper".

The powerful impact force of the rapid impact compactor exerts an impact compaction function on the subgrade, the original water and air in the soil are squeezed out, the soil particles are rearranged under the strong impact force, and fewer particles are squeezed into the gap of large particles to form secondary settlement, so that the soil forms a plate with high density, improves the strength and bearing capacity of the subgrade, and effectively reduces the settlement deformation of the Subgrade after construction.

At the same time, the rapid impact compactor has the characteristics of high frequency. The high-energy impact force impacts the ground periodically and continuously, producing strong shock waves, and has the propagation characteristics of seismic waves downward. The resulting impact compaction function can continuously increase the compactness of the deep underground layer, making the pressed earth rock fill closer to the elastic state, showing the technical advantages of overcoming the hidden dangers of earth rock subgrade.

Taking the subgrade settlement of 100mm after reinforcement by 36kj rapid impact compactor as an example: 70% of the set settlement occurs within 2m of the effective compaction depth, and the rest occurs within 4m of the affected depth, the average compressibility of the soil within 2m below the surface layer is increased by 3.5%, and the average compressibility of the soil within 2~4m below the surface layer is increased by 1.5%.

After using the rapid impact compactor to construct the subgrade, the effect is very good, which can make the subgrade form a dense and uniform reinforcement layer, and reduce the natural settlement rate after construction. The compactness of the Subgrade after construction can be increased by about 1~6% compared with the subgrade compaction before construction, and the compactness can be increased to about 98%. The rapid impact compactor can effectively reduce the post construction settlement value of the subgrade and improve the service life of the highway subgrade.