The DXTJ-05 bid section of The Delingha-Xiangride Expressway in Qinghai has a total length of 23 kilometers, including 1 bridge, 6 bridge passages, 14 culvert passages, 21 backfills on the back of the bridge and culvert platform, and 1 Rapid Impact Compaction used in this section.
Under the action of gravity and hydraulic pressure, the Rapid Impact Compaction compacts the soil, and under the action of the hydraulic cylinder, under the traction of the loader working device, it is flexible and flexible to compact different positions to meet the requirements of single-point or continuous compaction compaction area.
In order to better control the effect of ramming, the Rapid Impact Compaction test was first carried out. The test site selected the no. 7 abutment of the central pile of the lot K87+910 Sulen gol Bridge. The abutment backfill soil is gravel soil, partial clay, with little water content and large sand content. The test site adopts HC36 Rapid Impact Compaction, which arranges the backfill of the completed No. 7 abutment according to a certain spacing density, improves the compaction of the backfill of the platform, and minimizes the problem of bridge head jumping during highway operation.
First of all, the foundation on the back of the abutment should be flattened and rolled, and the work site should be flat. The tamping range is identified with a white-gray line, and then the initial elevation of each point is measured according to the number. The Rapid Impact Compaction is in place according to the marked position, so that the rammer hammer of the Rapid Impact Compaction is aligned with the point. According to its compaction capacity, the compactor is divided into strong, medium and weak three compactors adjusted to the strong gear compaction of each compaction point of the strong gear compaction is 6 to 9 times, and 3 times compaction is a group. The relative settling difference between the last group and the previous group is less than 10 mm. According to the results of field tests, it can be seen that the strong gear 6-9 strike operation can enhance the quality of the bridge and culvert back and greatly improve the operation efficiency.
Due to the large impact depth of the compaction process, after the reinforcement of the Rapid Impact Compaction, the overall settlement of the back of the bridge and culvert platform was 32mm, eliminating the problem of insufficient post-work settlement and rolling effect during the construction process.
The Rapid Impact Compaction has good maneuverability, controllability and high efficiency, which can evenly improve the deep compaction of the packing. Significantly improved and improved the phenomenon of bridge head jumping after the opening of highway bridges and culverts.
