除尘灰基泡沫轻质土耐久性能

Durability Performance of Foamed Lightweight Soil Based on Dust Removal Ash

摘要: 为评估除灰基泡沫轻质土的耐久性能，以钢铁冶炼产生的除尘灰为主要原材料，文章开展了干湿循环和冻融循环试验。试验结果表明，轻质土在经历干湿循环和冻融循环后，试样表面出现剥落，边角损坏；水泥基泡沫轻质土的耐水性优于除尘灰基泡沫轻质土，循环后的质量含水率更快趋于稳定，密度越大，轻质土的质量变化率越小；水泥基泡沫轻质土的抗干湿和冻融循环能力更强，不同密度的除尘灰基泡沫轻质土干湿循环后强度分别衰减至69.3%~94.3%，冻融循环后衰减至68.2%~93.4%；水泥基泡沫轻质土则分别介于87.3%~96.6%和87.4%~94.1%；轻质土密度越大，强度衰减程度越小，耐久性能越好；除尘灰基泡沫轻质土的耐久性能良好，在实际应用时，为满足工程要求，建议采用密度 > 800 kg/m³，除尘灰掺量 < 50%的泡沫轻质土。

Abstract: To evaluate the durability of sintered dust foamed lightweight soil, sintered dust generated from steel smelting was used as the main raw material. Dry-wet cycling and freeze-thaw cycling tests were conducted. The test results showed that after undergoing dry-wet and freeze-thaw cycles, the surface of the lightweight soil samples experienced peeling and damage at the edges and corners. The water resistance of cement-based foamed lightweight soil is superior to that of sintered dust foamed lightweight soil. After cycling, the moisture content of the mass tends to stabilize more quickly, and the greater the density, the smaller the rate of change in the quality of the lightweight soil. Cement-based foamed lightweight soil has stronger resistance to dry-wet and freeze-thaw cycles. The strength of sintered dust-foamed lightweight soil with different densities decreased to 69.3%~94.3% after dry-wet cycling and to 68.2%~93.4% after freeze-thaw cycling. In contrast, cement-based foamed lightweight soil ranged between 87.3%~96.6% and 87.4%~94.1% respectively. The greater the density of the lightweight soil, the lesser the degree of strength decay, indicating better durability. Sintered dust-foamed lightweight soil has good durability. For practical applications, to meet engineering requirements, it is recommended to use foamed lightweight soil with a density > 800 kg/m³ and a sintered dust content < 50%.