Effective And Economical 

To avoid serious and potentially expensive problems due to liquefaction, it is advisable to densify loose soils and to provide a drainage path for dissipation of pore pressures before they reach dangerous levels. In most cases Nilex earthquake drains are the most effective and economical solution available for mitigation of liquefaction in loose, cohesionless soils.

Traditional methods such as jet/compaction grouting, dynamic compaction and vibro-replacement have been used to densify/stabilize potentially liquefiable soils. Although such methods are moderately effective in clean sand, they lose effectiveness as the fines content of the soil increases. In addition to being disruptive and often cost-prohibitive, these methods also do not contribute the added benefit of drainage.

A Combination Of Drainage And Densification 

Nilex Construction has applied its innovation and decades of experience in the vertical prefabricated drain and geosynthetics industry to the mitigation of liquefaction. Earthquake drains are installed with a vibrating mandrel into loose sands and silty-sands. The vibratory installation densifies the soils, increasing their cyclic shear resistance, while the drain provides a path for the rapid dissipation of earthquake-generated excess pore pressures. The combination of drainage and densification is the most conservative approach to liquefaction mitigation and is employed in over two-thirds of ground improvement projects in Japan.

Increased Discharge Capacity

The discharge capacity and flow rates available in a 100 mm (4in.) Earthquake Drain are far greater than in a traditional stone column where flow is governed by Darcy's law (porous media). Since drainage must occur in a matter of seconds during an earthquake, this large flow capacity is absolutely essential.