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What are the construction procedures that allow the mitigation of potential problems due to water in a retaining wall?

To be more specific: I'm talking about reinforced concrete walls.

The cases of water are: if I'm studying a reinforced concrete wall such that the soil is not saturated, and it rains so that the soil is saturated or if the water table level rises.

What are possible solutions? I'm looking for general solutions.

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    $\begingroup$ This is an incredibly broad question. Is there any way that you can be more specific? What type of water problems are you looking to know more about? Why type of retaining wall are you dealing with? Etc. $\endgroup$ – William S. Godfrey- S.E. Apr 5 '15 at 12:06
  • $\begingroup$ Also, don't assume that everyone knows what your abbreviations mean. Does RC stand for reinforced concrete or something else? $\endgroup$ – Fred Apr 5 '15 at 14:10
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Design

In design, the presence of water behind the wall can have two effects. It can cause additional force to be applied to the wall from hydrostatic pressure, or its presence can cause the soil characteristics to change.

Changing soil properties has the most effect on clayey soils. Relatively dry clay will have cohesion and reduce the force on the wall. Wetter clay will lose this cohesion and apply more load to the wall.

The way that the wall is designed will effect how the water needs to be handled. If the wall was designed to for the effects of water all the way up the wall, then nothing may need to be done. If it was designed for only a certain height of water, then this must be assured.

Removing water

Depending on the volume of water that is expected and the source, a few different methods of water removal can be employed:

  • Weep hole
  • Perforated drain pipe
  • Surface water diversion
  • Dewatering wells

Weep holes are small holes through the face of the retaining wall. These allow any water that is trapped behind the wall to slowly drain out. They are best for small volumes of water. They are often installed in all walls as a minimal level of assurance that water will not be trapped behind the wall.

Perforated drain pipes are usually installed at the base of a wall in combination with free draining fill or geotechnical fabric. They can drain larger volume of water, but the connection details and where the outflow is located need to be investigated.

Surface water diversions may include ditches or paved areas that keep surface water from running down a slope and being contained behind the wall. This method helps where ground water is less of a concern when compared to runoff.

Dewatering wells are only an option that is considered where the wall must be built below the groundwater level and where the force from the water can not be designed for. The wells have pumps that lower the ground water elevation in the area. These can pump large quantities of water, but they require constant monitoring and power.

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  • $\begingroup$ One possible addition to these excellent recommendations is to design and install the weep holes so they are not at risk of being blocked by sediments in future, i.e. filter media in the vicinity of the weep holes and/or filter fabric. $\endgroup$ – AsymLabs Oct 10 '15 at 20:29

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