Continuous dynamic compaction control (cdcc) has been under development by the federal german railroad authorities since 1985. The method can be used with vibrating compaction rollers of varying size and weight by measuring and recording the vertical acceleration pulses at the vibrating drum of the roller. The data are fed into a computer unit that combines the readings at the drum with other test data as the roller proceeds along the compaction area, and a continuousrecord of compaction data will be provided along the path of the compaction unit. Presented in this paper are the state of the art and first experiences in applying the cdcc method to the earthworks of asection of the new high-speed railroad track to be constructed between mannheim and stuttgart, west germany. The following advantages are expected to be realized from the use of the new compaction control method: (a) previously used sampling methods could not provide full coverage of the construction area, and failures have occurred because of insufficient compaction data; (b) previously used spot measurements interrupted the flow of construction work extensively, thus limiting the number of samples that could be taken economically; and (c) cdcc provides a continuous compaction record, avoiding the repetition of unnecessary compaction passes and providing a more uniform compaction of the area at lower costs. This paper appears in transportation research record no. 1309, Geotechnical engineering 1991.
Abstract