Experimental Study on Simulation Filling of New Underwater Cementitious Filling Material (NWC-FM)

To solve the problem of waste slag treatment slurry shields, a reuse scheme in which shield mud is used to replace traditional karst cave grouting filling material proposed; thus, new type underwater cementitious (NWC-FM) developed. NWC-FM convenient, inexpensive, and environmentally friendly. Its mix proportion designed, its mechanical performance tested. According characteristics caves, semiclosed pressurized simulation box designed manufactured simulate processes at construction sites, an test carried out. The results show that fluidity good, strengths samples three groups proportions meet requirements field construction. poured shows good fluidity, cohesion, nondispersibility, self-leveling, self-compacting. After each pouring material, 2∼3 cm isolation layer eventually forms on surface due action additives, can effectively block contact between water ensure flatness material. average compressive strength consolidated core 7 d, 14 28 d are 0.56 MPa, 0.72 0.79 respectively, meeting technical sites. has strong nondispersibility moderate strength, well during urban subways. Additionally, as low-cost friendly will greatly reduce project cost minimize environmental pollution.