Abstract
This paper investigates the backfill grouts included flyash, and the result of backfill grouting in the construction of shield-tunnel. The quality of this flyash, utilized for this grouts, was below to JIS. Putting stress on bleeding ratio and flow value in workability of the grouts, the mix proportion of the grouts was settled by design of experiments. As a result, the grouting pressure went up and was over the capacity of the grout pump, but it was possible to convey the grouts 530m from the plant. And the ratio of the grouts to the tail void was 130% in diluvial ground.
