In an underground installation, the external soil load above a buried flexible pipe causes a decrease in the vertical diameter and a corresponding increase in the horizontal diameter of the pipe. The horizontal movement of the pipe walls into the soil material at the sides of the pipe develops a passive resistance that acts to help support the external load. The resistance of the soil is affected by the type of soil and its density and moisture content. The higher the soil resistance, the less the pipe will deflect. Proper installation techniques are necessary to develop the passive soil resistance required to prevent excessive pipe deflections.
Above ground installations can be roughly divided into two categories;
a) lines which are laid directly on the surface of the ground
b) lines which are hung or supported as in a typical plant In case-a, it is anyway advisable to support the pipe by means of wooden or concrete sleepers, in order to avoid pipe damage by stones and other sharp objects.
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