关键词: 兰州地铁;砂卵石;同步注浆;浆液配合比

Abstract: The slurry performance of synchronous grouting can be better controlled by shield tunneling in Lanzhou Metro under the Yellow River Sandy Cobble Stratum.The performance of slurry grouting in sand and gravel stratum was investigated by 8 groups of different proportioning.The slurry density, slurry fluidity, slump, consistency, setting time, water pouring test, anti water dispersion test and water separation rate and compressive strength were tested.Get the bentonite grout improves the stability of the pump;adding clay powder,the grouting cohesive capacity increases,improves the overall size and water resistance,but the addition of clay powder slurry, the slurry fluidity decreased, water content and clay content are the main factors of slurry condensation time and liquidity.The proportion of the obtained slurry is as follows:water 25% to 30%, bentonite 6%, cement 6% to 7%, fine sand 35% to 40%, clay powder and fly ash 20%to 25%.This will provide reference for shield tunneling through the Yellow River sand gravel stratum.

Key words: Lanzhou metro;sand gravel;synchronous grouting;slurry mixture ratio