Experimental Study On Disintegration Characteristics Of Compacted Soils

As a result of natural factors,the bank slope of the upper reaches of the Yangtze River experienced the process of "soaking,drying and soaking" as the water level rises and falls,and the soil on the banks of the slope was prone to disintegrate.The disintegrated soil was scattered in the water and accumulated naturally under the water,resulting in the obstruction of the river channel and the obstruction of the channel.The process of disintegration and development of compacted soil mass was actually the mechanical change process of compacted soil particles.Therefore,in order to study the disintegration mechanism of compacted soil,this paper was supported by the National Natural Science Foundation of China(No.51479012)“the deterioration mechanism and evolution process of periodically saturated sandstone and mudstone mixture”.The disintegration law of compacted soil was studied by a self-developed disintegration test device.The main research contents and achievements were as follows.(1)A compacted soil disintegration test device was developed.The system could monitor the mass change,volume change,disintegration rate,disintegration time and the underwater resting angle of the soil accumulated under the water after the disintegration of the compacted soil.(2)The variation law of disintegration time in compacted soil test was revealed.A disintegration test was carried out by means of a self-developed experimental device.The influences of water content,compactness,particle gradation and particle size on the disintegration time of compacted soil were investigated respectively.Based on the experimental phenomena in the disintegration process and the variation of the disintegration time of compacted soil,the main factors affecting the disintegration time of sandstone,mudstone,sandstone and mixed granular soil were analyzed respectively.(3)The variation law of disintegration amount in compacted soil test was revealed.In view of the influence of moisture content,compactness,particle gradation and particle size on disintegration rate,the close relationship between various factors and disintegration amount was revealed by accurate data monitoring in the experiment.For different particle types of soil,the main factors affecting disintegration rate were different.The main influencing factors of samples with different particle sizes were analyzed by experiment,observation and monitoring data(4)The change law of the underwater repose angle of compacted soil test was revealed.The height of the mound collapse accumulation after completion of the test disk,calculated the disintegration soil to form the angle of repose,and it summed up the moisture content,density,particle size,particle type and other factors affect the repose angle.The relation between the angle of repose and the amount of disintegration and the time of disintegration was determined.The main factors affecting the size of underwater repose angle were summarized by observing the experimental phenomena and monitoring data.