The Methods of Ground Water Control in Excavations explains in this post. These techniques use to prevent groundwater entering into construction like, piling for bridges, tunneling, marine structures, underground structures. The groundwater causes extreme geotechnical problems in excavations like sand running for most of the construction projects. These issues caused by groundwater increase construction budget and extend construction time.
Methods of Ground Water Control in Excavations
There are two major Methods of Ground Water Control in Excavation explains as follows,
- Pumping technique
- exclusion technique
1. Pumping technique
It is highly expensive by Utilization of large capacity pumps which are not economical to consider in the critical situations.
2. Exclusion Methods to Control Ground Water in Excavations
There is a number of techniques by which groundwater exclusion are obtaining:
Forming impervious barriers
Chemical consolidation for controlling groundwater in excavation
Groundwater control by compressed air
Freezing groundwater control.
In these, we provide methods to prevent groundwater entering in construction by using Forming impervious barriers.
3. Forming impervious barriers
In this technique, permeability reduces by creating an impervious barrier.
An impervious barrier with lower end close by expandable plug & upper end seals on the surface drives into the soil. And grout is force into the pipe and drive out the plug and wide fissures with grout.
Application
- Drill a hole in advance, insert a lance for grouting to carry out by a bottom-up method or top-down method.
- Gout upper part by a lance inserted into the hole. After its setting time grout lower part of the pipe.
- After grouting, preventing groundwater from entering into the excavation of piling, the normal procedure implies out for constructions.
Chemical consolidation for controlling groundwater in excavation
Chemical consolidation method is suitable for sandy gravels and fine grading sands. The most usual chemical material used for chemical consolidation is the sodium silicate.
Control Ground Water in Excavation by Compressed Air Method
There are several factors that motivate the application of compressed air to control groundwater in excavations. Compress air techniques are for controlling groundwater in excavations of tunnels and shafts.