Before spending the time and energy adding drainage to an existing retaining wall, make sure the wall is worth saving. If the wall is leaning out or there are cracks in the concrete, these could be signs of irr. These openings, known as weep holes, play a crucial role. They facilitate the drainage of trapped water behind the wall, helping to avoid excessive pressure that might cause cracks or even structural failure. Without these holes, water can accumulate and gradually weaken the wall.
[pdf] The standard method involves percussion drilling in which a drill is alternatively raised and dropped in the descending borehole. It is suited to the drilling of wells in any material from soft clay to the hardest rock.
[pdf] A common drill rig used for "Shot Hole Drilling" is the L.I.S (Low Impact Seismic) mounted on track carrier for operation in cut lines or environmentally sensitive area. Truck mounted drill or 4X4 buggy are utilized in the prairies. These drill rigs use water or air to assist the drilling.
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