Characteristics of Rubberized Loess‐Based Controlled Low‐Strength Material

Abstract A study investigates a rubberized loess‐based controlled low‐strength material (CLSM) that can be used as a backfill by adding loess and tire‐derived aggregate (TDA). The mixture was prepared to contain different amounts of rubber, excavated collapsible loess, cement, fly ash, water, and additives. A series of tests were made, including flowability, density, strength, bleeding, durability, and thermal conductivity by adjusting the rubber‐to‐loss ratio (R/L), water‐to‐aggregate ratio (W/A), binder‐to‐aggregate ratio (B/A) and fly ash to loess ratio (F/L). Results show that an Increased R/L ratio would reduce water demand, increase bleeding capacity, reduce compressive strength, and reduce thermal conductivity. Replacing part of the loess aggregate with TDA can reduce self‐weight and increase thermal insulation characteristics. The addition of fly ash as a mineral admixture can improve fluidity, reduce cement consumption, and increase long‐term strength. Finally, the mix design of backfill material suitable for seasonal frozen soil areas is put forward for construction reference.