Vertical drain (for ground improvement)
Vertical drainage can be used to accelerate the consolidation of impervious soils. Vertical drains are flat or round flexible plastic tubes. MENARD has developed its own range of drain installation equipment to cope with a wide variety of subsoil conditions. The picture below shows a static 45 m cable leader machine which can be equipped with a vibrator.
Sand or granular columns may also be used to provide vertical drainage, depending on the type and nature of the soil.
Commonly, a temporary embankment is used in conjunction with vertical drainage to pre-load th ground in order to reach a total primary consolidation and a guarantee of several decades concerning secondary consolidation.