Construction points of rapid impact compaction machine in Gansu, China: The points are evenly distributed along the center of the hammer with a distance of 1.5m. The layout range exceeds the filling range on the back of the table. The minimum distance between the edge of the rammer and the back of the table is 50cm.

Consolidate the whole process and test standards: integrate the construction of the construction site, and the winning bidder selects the platform back of the small bridge at the test site. The relative height of the back of the platform is 2m at this stage. Specifications of mechanical equipment: HC36 rapid impact compaction, net weight of rammer is 3t, type 36, stroke arrangement is 1.2m, ramming potential is 36kJ, and the diameter of rammer plate is 1.0m. According to the work experience, this test selects 3 gears of the automobile, and accumulates 3 hammers each time for tamping work. After every 3 hammers, select the relative elevation DSZ3 type level meter to accurately measure V, obtain the matching cumulative settlement and relative settlement, and select the power The touch test conducts different tamping frequency positioning points for the bearing capacity of the left and right surfaces before and after tamping. Finally, the overall settlement of the backfill surface is measured on the compacted surface.

Analysis of the construction results of rapid impact compaction in Gansu, China: According to the analysis table of the combed test data, it can be seen that the settlement caused by tamping increases with the increase of the number of ramming hammers. The optimal control of the two is related to the increase in the settlement. slowing shrieking. According to the on-site inspection, it was found that most of the damaged protrusions occurred near the tamping point. The relative settlement of the first three hammers during the whole compaction process is relatively large, while the total settlement of the first nine hammers of the rapid impact compaction equipment is 53.12 of the total settlement. The cumulative settlement after the hammer accounts for 67%.4% of the total settlement, while The relative settlement from 13 to 15 hammers only accounts for 12.4% of the total settlement. According to the above research, when the winning bidder is tamping a similar working face, the tamping method of selecting 3-speed 9-hammer to hammer can exceed the specified actual tamping effect. The rapid impact compaction machine should not be over-tamped during the tamping process to prevent the lateral pressure of the nearby sand and soil protrusions and damage the original layered structure. According to the test data information, it is observed that the bearing capacity of the surface is increased by about 600kPa~90kPa after 9-12 blows. After the 9-hammer has been tamped by the 12-hammer, the tamping surface is smoothed and smoothed, and the design elevation is re-measured, and the overall tamping surface settles about 7 times cm~ 10cm.

1. According to the compaction conclusion, it is analyzed that the compaction work of the 3rd gear 9-hammer to 12 hammers of the hydraulic compactor can improve the compaction quality of the subgrade project and accelerate the post-construction settlement of the filled subgrade.

2. During the construction process, the winning bidder conducted tests according to the actual conditions of various regions, and it was determined that the 3rd gear, 9 hammers to 12 hammers, was the most suitable for compacting the vehicle gear and the number of hammers. It should be strengthened once every 2 meters of deep filling, and then the "three backs" should be strengthened. Tamping quality.

3. The reinforcement area shall be clearly defined according to the joint filling area of the "three backs" subgrade engineering.

4. If part of the settlement is too much, filling and tamping with 3 to 6 hammers can be given according to the actual situation, which is beneficial to the overall ground leveling of the workbench.

5. According to the compaction technology of the rapid impact compaction machine, the deep compactness of the filler can be symmetrically improved, and the actual effect is remarkable. It is especially suitable for the construction of narrow working faces such as "three-back" roadbed engineering joints, and is very worth promoting.