Diaphragm Wall
Commonly used in congested area for retention systems and permanent foundation works. They can be installed in close proximity to existing structures with minimal loss of support to existing foundations.
Diaphragm wall (also known as slurry wall) are basically deep trenches excavated in the soil into which reinforced concrete is placed. Excavation is accomplished by digging panels into the ground, while trench stability is maintained using bentonite or polymer slurries. Once excavated, three-dimensional reinforcement is set in the trench and followed by the placement of structural grade concrete using tremie pipes. The result is a structural wall system that not only provides temporary earth support but also provides permanent foundation system.
Contiguous Pile
Closely spaced bored piles can be used to form a retaining wall, perhaps for the construction of a deep basement or a cut and cover tunnel. The piles may be constructed so that they virtually touch each other (contiguous)
Secant Pile
Every other pile may be constructed, with their centers less than two diameters apart. Infill piles are then bored, cutting into the adjacent piles to form a continuous structure. To aid construction, the first set of piles may be cast with a lower grade of concrete. These may not be load-bearing and act as “SEALS” between the main load-bearing piles.
Sheet Pile
Sheet piles wall is constructed by driving steel sheets into a slope or excavation. Their most common use is within temporary deep excavations. They are considered to be most economical where retention of higher earth pressure of soft soil is required. An important advantage is that they can be driven to depths below the excavation bottom and so provide a control to heaving in soft clays or piping in saturated sand. Sheet piles are more costly and less adaptable to hard driving conditions, particularly where boulders or irregular rock surfaces occur.
Soldier Pile
Constructed using wide flange of steel H sections spaced about 2 to 3m apart and are driven prior to excavation. It consists of multiple piles spaced apart form each other to support a change of elevation. The piles are usually H beams installed in drilled shaft. Timber lagging is then installed between the H beams to restrain the soil between the piles. Deeper excavations may require tiebacks to be installed at the piles for additional support.
Soldier pile shoring is very versatile because the size of the piles and the spacing between them can be adjusted to site soil condition. In many cases, this is the most economical method of shoring.