关键词: 力学特性, 铁尾矿砂, 水泥土, 干湿循环, 强度损失

Abstract: In order to explore the mechanical properties and anti-deterioration ability of iron tailings cement soil, we conducted unconfined compressive strength test and wetting-drying cycle test to examine the influences of cement content, iron tailing sand content and number of drying and wetting cycles on the strength of iron tailings cement soil. Results demonstrated that a dosage of 20% iron tailing sand had a largest improvement effect on the strength of cement soil, improving by about 70%; a dosage of 40% iron tailing sand had a least enhancement effect. Dry-wet cycles had deterioration effects of varied levels on the strengths of plain cement soil and iron tailings cement soil: the strength loss of plain soil-cement was greater at the initial stage of cycle than that in the later stage and tended to be gentle gradually, while the strength loss of iron tailings cement-soil was small at the initial stage of cycle, and the strength deteriorated obviously after a certain number of cycles. The main reason for the deterioration of cement-soil strength is the stress concentration caused by the drying shrinkage and wetting swelling of pores.

Key words: mechanical properties, tailings of iron ore, cement-soil, wetting-drying cycles, strength loss