The loads generated by a traditional embankment can cause instability and differential settlement if the supporting ground has poor mechanical properties. These problems can usually only be avoided by means of costly, technically complex preliminary stabilisation works (preloading and drainage, piling, etc.).
The use of Laterlite Expanded Clay as the nucleus significantly reduces the weight of the embankment (up to 80%), enabling the cost of stabilising the founding ground to be partly or completely avoided.
By constructing the embankments using the load compensation method (replacing a volume of the heavy ground below the embankment with an equivalent volume of lightweight expanded clay) the loading on the ground is not increased (or is only increased by an extremely small amount), maintaining the original state of stress, even in embankments of considerable height.
- Reduced absolute and differential settlement of the embankment.
- Simple and rapid construction using ordinary site equipment
- Increased safety coefficient at the ultimate limit state of the embankment
- Possible to construct in technically or logistically complex situations
Light embankments in Laterlite Expanded Clay can be:
- uncompensated : on foundation ground with poor bearing capacity, the distributed load is reduced by exploiting only the beneficial effect of the lower specific weight of the material itself.
- compensated : if foundation ground with poor bearing capacity is partly replaced with expanded clay, this improves its mechanical characteristics and compensates either partly or completely for the imposed load of the new embankment.
A light embankment constructed with expanded clay can compacted in various ways, depending on the construction method :
After a load distribution layer has been spread:
- Spreading a load distribution and capping layer (of gravel or rockfill) followed by compaction with a roller;
- Interposing a geogrid, followed by compaction with a roller;
Directly on the layer of expanded clay:
- Using a plate compactor;
- By passing over it with a tracked vehicle (excavator/shovel)