Abstract:

In order to analyze the difference among drainage consolidation rules of different slurries in different strata during shield backfill grouting, the process of drainage consolidation of shield backfill grouting is simulated by a homemade experiment apparatus; and then the drainage consolidation rules of three kinds of typical slurries, inert slurry, hardness slurry and thick slurry, in different strata are studied. The results show that: 1) In the silty clay stratum, the drainage consolidation speed of the slurry depends on the infiltration degree of water in slurry. 2) In the siltyfine sandy stratum, the drainage consolidation speed of the slurry depends on the waterretaining property and water dispersion resistance of the slurry. 3) In the coarse sandy stratum with large permeability coefficient, the cohesive action of slurry particle has a great impact on drainage consolidation speed of the slurry in the early stages of consolidation; the strength of the slurry is greatly affected by the cementing materials after consolidation; and that is little affected by permeability coefficients of the strata. 4) The 7day strength of hard slurry increases by 30% compared to the 3day strength of hard slurry after consolidation; the strengths of inert slurry and thick slurry vary little after consolidation.

Key words: shield backfill grouting, consolidation property of slurry, types of slurry, process of consolidation