MECHANICAL PROPERTIES OF FOAMED MIXTURE LIGHTWEIGHT SOIL CONTAINING

轻质土技术已被广泛应用于工程建设中，以解决软土地基问题。该技术提供的主要优势是降低了地基土改良成本，并由于减少了地面荷载而缩短了施工时间。然而，之前的研究表明，野外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，有效地利用技术和工程设计来处理工业废物变得越来越重要。为了促进工业废物的回收利用，本研究描述了初始高温养护历史对含有粉煤灰和片状PET瓶废料的发泡混合物的无侧限抗压强度和微观结构的影响。比较了发泡混合轻质土与掺有粉煤灰和片状聚酯废料的发泡混合轻质土的性能。定量研究了粉煤灰和片状聚对苯二甲酸乙二醇酯(PET)瓶对发泡混合轻质土应力应变特性的影响。这些特性使火山灰和片状聚酯瓶废料可用作建筑材料。对内部结构的观察表明，随着初始固化温度的升高，无侧限抗压强度的下降是由于加热引起的结构变化，在这些结构中，均匀分布的小气泡相互连接并形成大空腔。另一方面，采用由两个双曲线模型组成的应力-应变关系，研究了泡沫混合轻质土的力学行为。具有高温历史的泡沫混合轻质土应力应变关系的观测结果与数值模拟结果吻合较好。随着研究的深入，煤灰渣和片状聚对苯二甲酸乙二醇酯(PET)瓶子废料的潜在利用潜力可以得到提炼。

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.