Method of temporarily shoring and permanently facing and excavated slope with a retaining wall

A method of temporarily shoring and permanently facing an excavated slope under an existing bridge structure comprising the following steps:

• excavating a slope beneath the existing bridge structure in successive sections to form exposed slope faces;
• forming a temporary shoring wall beneath the existing bridge structure by
• shoring up the exposed slope face of each successively excavated section with temporary soil nails and at least one layer of pneumatically applied concrete,
• thickening said at least one layer of pneumatically applied concrete to form reinforcement elements, said reinforcement elements including reinforced steel bars which extend outwardly away from said exposed slope faces,
• installing tieback through said reinforcement elements and testing, tensioning and securing said tie backs against said reinforcement elements;
• and
• forming a final retaining wall beneath the existing bridge structure by placing an outer layer of reinforced concrete over said temporary shoring wall and tensioned tieback, such that the outer layer of concrete ties to the tieback via the reinforced steel bars and the final retaining wall is fully supported by the tiebacks through the reinforcement elements and the reinforced steel bars.