Dilatancy (granular material) dilation. Because of dilatancy, the angle of friction increases as the confinement increases until it reaches a peak value. After the peak strength of the soil is mobilized the angle of friction abruptly decreases. As a result, geotechnical engineering of slopes, footings, tunnels, and piles in such soils have to consider the potential decrease in strength after the soil strength reaches this peak value. Poorly / uniformly graded silt with trace sand to sandy that is non-plastic can be associated with challenges during construction, even when they are hard. These materials often appear to be granular because the silt is
Sand equivalent test Sand equivalent test The sand equivalent test quantifies the relative abundance of sand versus clay in soil. It is measured by standardized test methods such as ASTM D2419, AASHTO T176, and EN 933-8. The test is used to qualify aggregates for applications where sand is desirable but fines and dust are not. A higher sand equivalent value indicates that there is less clay‐like material in a sample. During the test, material from the test specimen that can pass through a No. 4 sieve is mixed with solutions of calcium chloride, formaldehyde and glycerin in a cylinder. The content is then