城市固体废弃物本构模型的研究现状及展望

城市固体废弃物(MSW)是由多种无机和有机成分组成的复合材料,具有高压缩性和可降解性。随着时间的变化,基本的物理力学特性发生变化,与传统土体相比,性质差异较大。城市固体废弃物的本构模型对于垃圾填埋场中土工问题的研究极其重要,考虑不同因素的影响,系统总结了国内外一些学者对MSW本构模型的研究现状,指出已有的研究成果主要考虑了荷载引起的瞬时变形、机械蠕变、生物降解、纤维物质的加筋作用等,但这些都是考虑单个因素或者将几个因素简单叠加的本构模型,并未考虑不同因素的耦合作用。结合土体本构模型的发展特点,指出了今后城市固体废弃物本构模型的研究方向和发展趋势:应当综合考虑各种因素对MSW应力-应变关系的影响,从工程实践出发,通过岩土工程、环境工程、化学工程和生物工程等学科的交叉寻求突破,形成考虑生化反应-骨架变形-水气运移-溶质迁移耦合作用的理论框架。

Research status and prospects of constitutive models for municipal solid waste

This paper summarizes the research status of municipal solid waste (MSW) constitutive models, which is very important to study geotechnical problems in landfills. MSW consists of a variety of inorganic and organic components and has high compressibility and biodegradability; and its physico-mechanical properties gradually change over time. In these existing models, it can be seen that MSW instantaneous deformation, mechanical creep, biodegradation, fiber reinforcement are taken into account. Unfortunately, various influence factors are considered in some models, respectively, or only are simply added in other models. The coupling effects of these factors are not taken into consideration. Furthermore, the future studies and development trend of MSW constitutive models are proposed based on the study of the constitutive models of soils. A variety of factors that influence the stress-strain behavior of MSW should be considered. Meanwhile, a breakthrough should be sought by combining the theories of geotechnical engineering, environmental engineering, chemical engineering and biological engineering. Finally, the theoretical framework for biodegradation, mechanical deformation, fluid flow and contaminant transport in MSW can be established.