Transcript for Hoover Dam Construction, segment 10 of 17
From the mixing plant concrete was dispatched to all sections of the works, and because of the widely varying conditions prevailing, various types of containers and methods of transportation were involved. Motor trucks and electric trains were utilized as carriers, and containers varied from the eight cubic yard capacity bottom dump buckets to the four cubic yard capacity transit mixers. The latter were used on long hauls where it was necessary to agitate the concrete in transportation to prevent segregation of the mix. However, the major portion of the concrete handled on the project was carried in the eight cubic yard buckets and transported from the mixing plants by electric train. A system of nine aerial cableways spanning the canyon from rim to rim and anchored at either end to movable towers, was utilized to carry the concrete and other materials from the points of train or truck delivery to the dam and other structures on the project.