【摘要】 城市垃圾填埋场是环境岩土工程研究领域面临的新问题,对其地震变形机理尚缺乏深入的了解,迄今难以建立专门的地震稳定性评价体系。针对垃圾填埋场的工程特性,精心设计8个大比尺模型进行振动台试验,采用类比方法并运用一些试验新技术,再现垃圾填埋场的震害现象,揭示沿基础衬垫层和封顶覆盖层的接触面发生较大相对滑移是地震作用下垃圾填埋场的主要破坏模式,其中封顶覆盖层的破坏模式再次印证"双滑楔体"假定;由于垃圾土低密度、高压缩性,以及垃圾填埋场具有特殊的防渗层结构等特点,垃圾堆体内部不容易出现明显的滑裂面;定性和半定量地考察、研究封顶覆盖层和基础坡比、垃圾堆体密度、接触面强度参数、地震波频谱特性等因素对垃圾填埋场地震响应及其破坏的影响。更多还原

【Abstract】 Due to lack of understanding in mechanism of seismically induced deformations of municipal waste landfills, it is difficult to develop special methods to evaluate the seismic stability of landfills. Applying an analogy method and some new testing techniques,eight physical model experiments of landfills were conducted on shaking table to investigate the mechanism of seismically induced deformations in landfills. It was revealed that excessive relative displacements within the specific interfaces of liner and cover systems were the primary failure patterns of landfills in earthquakes, whereas waste collapse was seldom a concern because of such characteristics of landfills as low density, high compressibility of MSW and the existence of a liner system. Furthermore, the two-part wedge direct sliding mechanism, proposed by Ling et al., has been validated by the damage phenomena of the landfill cover in the test. The shaking table tests also qualitatively or semi-quantitatively studied the relative importance of the factors that influence the seismic response and earthquake damage patterns of landfills, including waste density, base and cover slopes, strength parameters of interface and characteristics of input motions.更多还原