Effect of Specimens’ Height to Diameter Ratio on Unconfined Compressive Strength of Cohesive Soil

Abstract The undrained shear strength (Su) and cohesion (Cu) of cohesive soils are frequently determined using an unconfined compression test. However, the test results heavily dependent on specimen size. This causes uncertainty in geotechnical analyses, constitutive models, designs by overestimating or underestimating soils. Therefore, study aims to assess effect height-to-diameter ratio compressive (UCS) soil. soil was tested a compacted cylindrical at maximum dry density optimum moisture content with height diameter (H/D) 1–3 for 38, 50, 100 mm diameters. Disturbed sample specimens were considered laboratory program. Accordingly, standard Proctor compaction determines classification characteristics. performed undisturbed remolded states various diameters investigate variation H/D ratio. revealed that soil's value drops rapidly ratios specimens’ increases. UCS stable from 1.75 2.25. As increased, peak axial strain decreased. Similarly, gap between strains smallest most significant decreased increase diameter.