【作者】 黄文竞；

【导师】 张季如；

【作者基本信息】 武汉理工大学 ， 岩土工程， 2007， 硕士

【摘要】 目前国内对颗粒破碎的研究主要集中在低应力水平下的静、动土力学性质上，对高应力水平下的工作开展甚少，而对石英砂的颗粒破碎研究则更不多见。本文结合单向压缩试验，对石英砂的压缩机理进行了探讨，并就颗粒破碎的影响进行了详细分析。主要工作如下：首先，在综述砂土颗粒破碎的研究历程的基础上，对本次试验所用的石英砂的基本物理性质以及矿物成分进行了阐述，根据试验目的和要求，设计研制试验装置；对试样制备、试验设备、试验方法和试验中可能遇到的问题进行了详细的说明。简要总结了无粘性土的压缩模型和影响无粘性土压缩特性的因素。在对石英砂大量不同终止压力下的单向压缩试验的基础上，对石英砂压缩特性进行了探讨。认为石英砂在高应力单向压缩下的变形绝大部分为塑性变形。笔者对试验前后试样进行颗粒分析试验，运用Hardin提出的相对破碎对压缩作用下的破碎特征进行描述，并就相对破碎与颗粒粒径、颗粒级配、应力水平、应变关系进行了探讨。得出以下结论：天然石英砂颗粒在高压应力下会发生明显的破碎现象；颗粒破碎率随所受压力和颗粒粒径的增大而增加，且破碎使得颗粒级配向良好的方向发展，级配良好的颗粒的破碎率较低。石英砂颗粒破碎与塑性功间呈二次曲线关系。最后，对本文的研究成果进行了总结，并就石英砂的研究方向做出了展望。更多还原

【Abstract】 At present, the domestic studies of particle breakage mainly center on the mechanical property of dead and dynamic soils under the low stress. However, little work has been done under the high stress, the particle breakage study on quartz sand is much few. In order to investigate the compression mechanism and makes a detailed analysis on the influence of particle breakage, The unidirectional compression test was carried. This investigation and analysis owns relatively important meaning on developing and improving the mechanical property study of natural quartz sand, guiding the realistic engineering design, construction and safety inspection, and enhancing the study level of particle breakage. The main works are shown as follows:Firstly, based on summarizing the study history of sand particle breakage, the paper expounds the basic physical property and mineral components of the natural quartz sands used in this test, design and develop the test device according to the test objective and requirement, and makes a detailed explanation on the test equipment, test sample preparation method, test procedure, the preparation steps and possible problems in the test.The compression model and the course of compression characteristic are being summarized briefly. Base on the massive one-dimension compression tests in different ending Pressure, the compression characteristic of natural quartz sand is being studied. The overwhelming majority compression is plastic deformation.The author makes the particle size analysis test on the samples in all tests, uses the relative breakage put forwards by Hardin to describe the breakage characteristics under the compression, and investigates the relative breakage and particle size, particle composition, stress level, and stress-strain relationship. It is shown that the particle breakage grows up with the increasing of pressure and the diameter of particle, better constitution leads to lesser the breakage rate, moreover the breakage rate and plastic work has a repeated curve relation.Finally, the author summarizes the study findings and look forward to the study direction of the quartz sand.更多还原