BACKFILLING MATERIAL Russian patent published in 2004 - IPC

FIELD: well construction technology.

SUBSTANCE: material includes Portland cement, expanding admixture, gypsum, hardening accelerator, plasticizer, as an expanding admixture has at least one admixture from group: alumina cement, sulphoaluminate cement, aluminate-containing slags from production of ferrotitane, ferroboron, secondary remelting of aluminum, as plasticizer having mixture of triethanolamine and silica-containing admixture of multifunctional effect at ratio from 1:1 to 1:10 and additionally has lightening admixture at following ratio of backfilling material components in percents of mass: expanding admixture - 2-15, gypsum - 7-9, hardening accelerator - 2-8, said plasticizer - 0.3-0.8, lightening admixture - 3-10, Portland cement - the rest. As hardening accelerator backfilling material may contain chloride salt of alkali or alkaline element. As lightening admixture alumosilicate microspheres or microsilica may be used, or expanded vermiculite, or expanded perlite.

EFFECT: higher sedimentation resistance, no water discharge, longer thickening time.

2 tbl