【作者】 沈杰；

【导师】 洪振舜；

【作者基本信息】 东南大学 ， 岩土工程， 2015， 硕士

【摘要】 真空预压技术已经应用于高含水率疏浚泥堆场的地基处理中。但是,在实际工程中不时遇到处理效果不佳的问题,主要呈现真空加固后土体强度沿排水板径向衰减的“土桩”现象,排水板与排水板的中间区域土体处理后强度仍非常低。本研究为了探索引起“土桩”问题的主要影响因素,进行室内高含水率疏浚泥的模型试验研究,主要的研究工作与成果如下：(1)针对三种不同液限的疏浚泥进行不同的真空压力和不同初始含水率的室内真空预压模型试验,探索真空预压处理效果随初始含水率、土体液限和真空压力的变化规律。(2)通过测试疏浚泥中径向真空度,研究了真空度在径向的衰减性状,分析了初始含水率、土体液限和真空压力对真空度衰减的影响,并提出了各不同试验条件下真空度在径向衰减的定量关系式。(3)通过测试土体沿径向的含水率和十字板剪切强度,分析土体含水率和剪切强度在各不同试验条件下的径向变化规律。(4)通过测试土体黏粒含量在径向的分布,分析了各不同试验条件下径向细颗粒的移动性状,进而明确初始含水率、土体液限和真空压力对对细颗粒移动的影响。更多还原

【Abstract】 Vacuum preloading method has been widely applied in the improvement of reclaimed land with dredged clays at high initial water contents. In the engineering practice, it turns out that the treatment often does not meet the design requierments. The phenomenon known as "soil pile" often occur, showing the decreasing in shear strength along the radical direction around the PVD. The strength at the middle zone among the PVDs is very low, almost equal to the strength of dredged clays before treatment. In this study, model tests of vacuum preloading on dredged clays were performed for investigating the main factors responsible for the phenomenon of "soil pile";(1) Model tests of vacuum preloading on dredged clays were conducted with different initial water content, vacuum load and dredged clays, to explore the effect of experimental factors on the vacuum treatment effect.(2) According to the results of the radical vacuum degree in the dredged clays, the attenuation of radical vacuum degree and its quantitative relationship equation is obtained. In addition, the influence law of different experimental factors is also discussed.(3) According to the results of the radical distribution of soil water content and vane strength, the influence law on the vacuum treatment of experimental factors is obtained.(4) According to the results of the change of radical clay content after test, we find out at what conditions the fine particles will move towards the PVD and its influence of different experimental factors.更多还原