Vacuum Consolidation Method (VCM)
Vacuum Consolidation Method ( VCM ) is for soft ground improvement, using atmospheric pressure as a temporary surcharge for Soil Consolidation.
Why VCM ?
Save fill material cost as vacuum pressure at -80 kPa is acting as the 4-meter height of surcharge preloading (If soil density = 20 kN/m3)
- Reduce overall soil improvement and construction period, unlike the conventional PVD method that the surcharge can not be filled all at once due to outward lateral displacement and the surcharge in VCM can be filled above the VCM system during the consolidation process
- Effectiveness of improvement is higher, as vacuum pressure is transmitted evenly throughout PVD, making the improvement performance is consistent
- Lateral movement is more controllable when conducting improvement beside existing infrastructures. As vacuum suction exerts inward into the subsoil, unlike surcharge preloading where an outward force is exerted.
Actually, stability increase is another advantages, which is mostly not drag much attention on it. Due to isotropic vacuum pressure, the ground can be improced, especially the shear strength increased and much stable after month VCM operation;
VCM has been successfully applied to many traditional field, such as highway, port, airport, manufacturing plant, etc
- Fasten consolidation period
- Less construction material mobilization