干湿循环作用下废弃泡沫轻量土水稳定性试验研究

Water Stability of Light Weight Soil Mixed with Waste Foamed Beads under Dry Wet Cycle Conditions

为了研究干湿循环条件下轻量土的水稳定性,通过密度试验、无侧限抗压强度试验和质量损失率试验,研究了轻量土的物理特性和力学性能。研究发现,轻量土的密度、强度和质量在长期干湿循环作用下具有很高的稳定性,其中强度还出现了一定程度的增长。这是由于轻量土中的水泥发生水解水化反应及轻量土各组分之间的相互作用,使土体的结构性逐渐增强,最终形成一个致密而稳定的网络状胶结结构,来抵抗干湿循环环境产生的侵蚀作用。在经受30次干湿循环作用后,密度的绝对变化量为0.02~0.06g/cm3,相对变化量为0.93%~4.47%。轻量土的密度在干湿循环作用下能够保持稳定,泡沫掺量对轻量土密度的影响较为显著。强度的绝对增长量为276.79~891.64kPa,相对增长量为71.46%~114.15%。其中,水泥掺量和含水量变化时,强度随干湿循环次数增加而变化比较敏感。质量损失率的变化范围大致在-1.00%~1.00%之间;随着干湿循环时间的推移,质量能够趋于稳定。即:轻量土在干湿循环作用下具有良好的水稳定性。

To research the water stability of light weight soil under dry wet cycle conditions, its physical characteristics and mechanical properties are studied by density tests, unconfined compressive strength tests and mass loss rate tests. The results show that the density, unconfined compressive strength and mass of light weight soil have a good stability under long term dry wet cycle condition, especially the unconfined compressive strength increases to a certain extent. Because of the hydrolysis and hydration of cement and the interaction of light weight soil＇s constituents, the materials form a network- like cementation complete structure, so it can resist the erosion of dry wet cycle environment. After 30 dry wet circles, the absolute change range of the density is 0.02-0.06 g/cm^3 , and the relative change range is 0. 93%-4.47%. Light weight soil＇s density can keep stable under dry wet cycle condition, the density of light weight soil is observably influenced by the foamed beads content. The absolute increment range of unconfined compressive strength is 276.79-891.64 kPa, and the relative increment range is 71.46%- 114.15%. When the cement content and water content are changed, the unconfined compressive strength varies sensitively with the increased dry wet cycles. The range of mass loss rate is --1.00-1.00%, the mass of light weight soil tends to be stable with the increasing of dry wet cycles. In a word, light weight soil has a good water stability under dry wet cycle condition.