Densification of deep loose granular soils to improve strength and stiffness.
Vibro compaction can provide a highly cost effective ground improvement treatment to strengthen, stiffen and improve drainage in loose/soft ground strata.
The process involves densification of loose granular soils by means of a hydraulic or electric powered vibrating poker sometime called a Vibroflot. The vibrating penetrates the ground vertically on a predetermined grid pattern such that the required compaction of the loose granular material occurs. The vibration probes can be suspended from a crane or mounted on a dedicated base rig and can typically achieve effective densification to significant depth where required.
The vibro compaction solution has a number of applications which can offer significant benefits on construction projects over loose granular ground strata. These include;
- Increased bearing capacity of the ground below shallow foundations and slabs.
- Reduced total and differential settlements of structures.
- Strength and stiffness improvement of the ground to limit the effects of disturbance and liquefaction during seismic events.
- Improved uniformity in variable fill or granular ground strata to limit differential settlements below pavements and hard landscaped areas.
Initially developed in Europe in the late 1930’s the vibro compaction technique has been used extensively on many ground improvement projects around the world. The system is particularly relevant where the problematical soil strata is a loose sand or gravel, treatment to depths in excess of around 6m are required and large scale site operations, that easily accommodate the heavy plant used, are proposed.
CMW work closely with specialist contractors who carry out vibro compaction works and we have the experience and knowledge required to carry out design, specification, testing, value engineering and review processes of these ground improvement solutions.