scope:

This European Standard establishes general principles for theexecution of diaphragm walls as either retaining walls or cut-offwalls. NOTE 1 This standard covers only structures constructed in atrench excavated with a support fluid or in dry conditions, wheresoil is removed and replaced by concrete or slurry and with wallthickness B ? 40 cm. NOTE 2 Diaphragm walls can be permanent ortemporary structures. NOTE 3 The following types of structure areconsidered: a) retaining walls: usually constructed to support thesides of an excavation in the ground. They include: 1) cast in situconcrete diaphragm walls; 2) precast concrete diaphragm walls; 3)reinforced slurry walls; b) cut-off walls: usually constructed toprevent migration of groundwater, clear or polluted, or of othercontaminants present in the ground. They include: 1) slurry walls(possibly with membranes or sheet piles); 2) plastic concretewalls. NOTE 4 Walls formed shallow vertical trenches (typicallyexcavations with a ratio of depth over thickness D/B < 5 or D< 5 m) are not covered by this standard.