Installation methods used for plastic pipes according to the compaction mode and materials:

• The pipe shall be surrounded with the same type of homogenous compacted material

• The layer around the pipe shall be divided into 2 areas, a primary and a secondary one, with different levels of compaction (pipes with diameters larger than DN 600 mm)



When two parallel pipes are placed in the same trench, the ground embedment rules remain the same. A distance by at least 150 mm wider than the widest side of the compaction equipment is recommended between the pipes.



It is forbidden to place HDPE pipes on the ground, even if additional technical measures are taken, because their structure is designed to withstand external loads via pipe-soil interaction.



The maximum burying depths described by Table 5 are indicative. They can be extended to greater burying depths in particular cases individually assessed by the designers.


The pipes shall be placed at the center of the trench, in order to allow a correct filling with material and a proper compaction. A stable bed and a good support layer shall be provided.

The recommended excavated depth should be 100 – 150mm below the level provided for the lower generating line of the pipe, in order to allow the execution of a properly compacted support layer, with a filling height of minimum 0.6 m.