Construction and Connection Method of Double-wall Corrugated Pipeline

Construction and Connection Method of Double-wall Corrugated Pipeline

1. Before using and installing the pipes, carefully check whether there are any damages in the process of loading, unloading, transportation and stacking. If damaged cracks, deformation and other defects are found, the pipes should be removed in time.

2. Flexible joints sealed with flexible fillers should be used to connect inspection wells with pipelines. The specific structure should be carried out according to the design requirements.

3. Attention should be paid to excavating trenches and making foundations:

1. The net width of groove bottom should be 0.6m plus the outer diameter of pipe.

2. Drainage measures should be taken during trench excavation to prevent the bottom of trench from being immersed in water.

3. Pipeline foundation must adopt gravel cushion. For general soil foundation, the thickness is 0.1m; for soft soil foundation, the thickness is not less than 0.2m. The specific method is according to the design requirements.

4. The foundation should be compacted and the surface should be smooth. The groove should be reserved at the interface of the pipeline foundation for interface operation. The length of the groove should be 0.4m-0.6m, the depth should be 0.05m-0.1m, and the width should be 1.1 times of the outside diameter of the pipe.

4. Lower pipe: When the groove depth is not too deep, it can be manually lifted into the groove. When the groove depth is more than 3 m, it can be slid into the groove by non-metallic rope. It is strictly forbidden to use metal ropes to hook the nozzles at both ends or roll the pipe from the side of the groove into the groove.

5. Interface operation

Rubber ring should be installed in the slot between the second and third ripple of the socket. The number of sealing rings installed depends on the design requirements. When two sealing rings are used, it is suggested that one ripple be separated between the two sealing rings.

After the interface is completed, the reserved grooves are filled with the same soil.

Installation of socket and socket pipes should be in the direction of downstream flow and upstream flow of the socket, in turn from downstream to upstream.

Pipeline should be laid in a straight line. The allowable rotation angle of the axes of two adjacent pipes should not be greater than 2 degrees. In order to prevent the aligned pipeline axis from moving when the joints are closed, the pipe stabilization measures must be adopted. The braided bags can be filled with sand and sealed and pressed on the top of the arranged pipes. The number of them varies according to the size of the pipes. After the pipe interface, the depth and axis of the pipe bottom should be checked to make it meet the requirements. If displacement, suspension and pull-out occur, the pipe should be reworked.

6. When backfilling, attention should be paid to:

1. Sand and coarse sand should be applied to fill the axillary angle (within 2D angle range).

2. Artificial backfilling must be used when the foundation is within 0.7m above the top groove.

3. The groove should be backfilled and compacted symmetrically in layers. The backfill height of each layer should not be more than 0.2m. No compacting machine should be used to compact the groove within the range of 0.4m above the pipe top.

4. The optimum compactness (%) of the backfill soil used in each part of the groove edge should be in accordance with the design requirements or the technical regulations of CECS122:2001. Steel plastic pipe