Groundwater in a permanant retaining structure

[Bomber1]

Please can someone advise me on the practical methods of controlling ground water pressure in a permanent earth retaining structure.

Everywhere i look there is info on temporary structures but not much for permanent.

Thanks in advance.

 

[SEshore]

If you are asking about water from surface runoff, one option would be to utilize drainage board and weep holes in your wall.

If you are asking about the water table, you need to either design for the hydrostatic pressure or find some means of permanently lowering and maintaining the water table.

 

[PEinc]

You may also need a method to temporarily lower the water table so that the permanent wall can be built without needing snorkles and a submarine.

http://www.PeirceEngineering.com

 

[Bomber1]

I am more concerned with water build up in the subsoil as thios will increase the pressures on the permanent structure and the methods to control this.

 

[SEshore]

Google "MiraDRAIN"

 

[csd72]

A french drain is the normal way to do it. If you have nowhere to naturally drain this then it could potentially drain to a pumping sump.

 

[Bomber1]

Thanks

Please can you elaborate on the pumping sump. Could this be installed as a permanent fixture? within the sub soil?

 

[GabionGuy]

Gabion retaining walls are free draining structure. If the gabion is an option, this will permanent remove the requirement to 'control' ground water pressures. There are none on a properly designed gabion retaining wall.

 

[PEinc]

Bomber1,

Please provide additional information. Without knowing what you are trying to do, we can't give you any assistance without guessing, which is a waste of all of our time.

What type of permanent retaining wall are you talking about? A sheet pile wall, a soldier beam and lagging wall with an attached facing, a soil nail wall, etc.?

I do not understand the following comment you made:
"I am more concerned with water build up in the subsoil as this will increase the pressures on the permanent structure and the methods to control this."

By subsoil, do you mean the soil beneath the wall? If so, how will this increase the pressure behind the permanent wall?

What need is there to control water pressure beneath the wall? Is your concern piping at the base of the wall? If there is that much water to retain behind the wall, what is to be built in front of the permanent wall and won't this structure be under water?

http://www.PeirceEngineering.com

 

[csd72]

Bomber1,

soory I should have stated that the pumped sump option is only appropriate if it is a transient source of groundwater such as rainwater infiltration and is definately not suitable for a permanent water table.

Use two pumps in case one breaks down.

A pump sump is just a pit below the floor