MECHANICAL PROPERTIES OF FOAMED MIXTURE LIGHTWEIGHT SOIL CONTAINING

轻质土技术已广泛应用于建筑工程中，以解决软土地基问题。该技术的主要优点是降低了地基土壤改良成本，由于减少了地面荷载，缩短了施工时间。然而，先前的工作表明，现场测试体内部的最高温度约为90摄氏度。另一方面，工业废物处理是一个日益严重的问题。因此，有效地利用工业废物处理的技术和工程设计变得越来越重要。为了促进工业废弃物的资源化利用，研究了初始高温养护历史对粉煤灰与片状PET瓶废弃物混合泡沫轻质土无侧限抗压强度和微观结构的影响。对泡沫混合轻质土与粉煤灰和片状PET废弃物混合的泡沫混合轻质土进行了比较。定量研究了粉煤灰和片状PET瓶对泡沫混合轻质土应力-应变特性的影响。这些特性使得煤灰和片状PET瓶废料可以用作建筑材料。对内部结构的观察表明，随着初始养护温度的升高，无侧限抗压强度的降低是由于加热引起的结构变化，均匀分布的小气泡相互连接形成大空腔。另一方面，采用由两个双曲模型组成的应力-应变关系模型研究了泡沫混合轻质土的力学行为。高温史泡沫混合轻质土的应力-应变关系与模拟结果吻合较好。粉煤灰和片状PET瓶废弃物的潜在用途可以通过进一步的研究来提炼。

Lightweight soil technology has been widely used in construction projects to solve soft ground problems. The major advantages offered by the technology are reduced foundation soil improvement costs and reduced construction time due to the reduced loading on the ground. Previous work, however, has shown the maximum temperature inside field test bodies reaches about ninety degree Celsius. On the other hand, industrial waste disposal is an increasing problem. It is, therefore, becoming increasingly important for technology and engineering design to be utilized effectively for industrial waste disposal.This study describes the influences of initial high temperature curing histories on unconfined compressive strength and microstructure of foamed mixture lightweight soil containing coal ash and flaky PET bottle wastes to promote industrial waste recycling. Comparisons are made between foamed mixture lightweight soil and foamed mixture lightweight soil mixed with coal ash and flaky PET wastes. The effects of coal ash and flaky PET bottle on stress-strain behavior of foamed mixture lightweight soils are quantitatively demonstrated. These properties make coal ash and flaky PET bottle wastes useful as a construction material. Observation of internal structures suggests that decrease in unconfined compressive strength with increased initial curing temperature is attributable to structural change induced by heating, in which small uniformly distributed air bubbles become connected to each other and form large cavities. On the other hand, a stress-strain relation that consists of two hyperbolic models was applied to investigate the mechanical behavior of foamed mixture lightweight soil. Reasonable agreement was obtained between the observed and the simulated results of stress-strain relation of foamed mixture lightweight soil with high temperature histories. The potential use of coal ash and flaky PET bottle wastes can be refined with further research.