Sedimentary Direction's Influence On Mechanical Characteristics Of Saturated Sand

Geological disasters such as debris flow and landslide and the geological action of soil will change the sedimentary direction of soil.At present,the sedimentary surface of sand is usually used as horizontal direction in triaxial shear test,the influence of sedimentary direction on soil strength is not considered,the study of soil strength has some limitations.In laboratory triaxial tests,the sedimentary surface of the sand sample is often horizontal or vertical,due to the limitation of the sample preparation method.This paper proposes a new sample preparation method-capillary saturation method,which uses the sand rain method to evenly scatter the sand in the model box,capillaiy saturation can keep the sand sample upright without lateral restraint and sampling along different sedimentary directions can be realized.Based on the sample preparation method,a series of triaxial consolidation drainage shear tests were carried out on the screened fujian standard sand to study the influence of sedimentary direction on the mechanical properties of sand.The direction angle of sedimentary was 0°,30°,45°,60°and 90°.The test results show that:(1)The sand sample particles prepared by the capillary saturation method are evenly distributed,and the experimental results are less different under the same conditions,have higher repeatability,and can be sampled along different sedimentary directions.(2)In the conventional triaxial compression test,sedimentary direction has a significant effect on the peak strength of sand,and there is no significant difference in the residual strength of sand.The peak strength of sand is similar when the direction angle of sedimentary a are 0°and 45°.The peak strength of sand is the lowest when the direction angle of sedimentary a is(45°-?/2),the axial strain reaching the residual strength is the smallest,and the peak strength is about 30%lower than the peak strength of sand with the direction angle of sedimentary a is 90°.When the direction angle of sedimentary is greater than(45°-?/2),the peak strength of sand increases with the increase of the direction angle of sedimentary,the dilatancy is more obvious.(3)Under different stress paths,the direction angle of sedimentary has different effects on mechanical characteristic of saturated sand.Figure Fifty-six table Two reference Fifty-five...