ABSTRACT
Before the excavation work of the ground in caissons was mechanized, pneumatic caissons were inefficient, labor-intensive means of subsurface construction. Excavating machines called caisson shovel were developed and they have been used efficiently for excavating the ground in large caissons since 1971. Through the improvements made to the various appliances associated with the use of caisson shovels, pneumatic-caisson technology has been remarkably renovated. Innovative unmanned excavation systems have been developed recently and they were utilized successfully in deep caissons. As a result of those renovations realized in pneumatic-caisson practices, the dreadful image associated with the cruel labor in the compressed-air work of the conventional pneumatic caissons was wiped out.
