Testing Study On Particle Breakage Mechanism Of Quartz Sand Under High Pressure Stress

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.