This paper presents an intensive series of laboratory testing results from vane shear and fall cone tests that were conducted on various clay–sand mixtures to understand the link between these methods which are often used for determining the undrained shear strength (s_u). Three different gradations (2.0–1.0 mm, 1.0–0.6 mm, and 0.6–0.3 mm) of rounded and angular sands were mixed with low-plasticity clay at ratios of 0%, 10%, 20%, 30%, 40%, and 50%. The results of the tests demonstrated that the s_u values obtained from the vane shear tests were found to be always higher than those obtained from the fall cone tests. It was shown that the sand content used in the mixtures changed the s_u parameters of the specimens significantly. The results indicated that the s_u values were significantly influenced by grading characteristics of the sands (d₁₀, d₂₀, d₃₀, d₅₀, d₆₀, c_u, c_c). The values of s_u were lower for the samples that had a larger size of sand grains. Finally, shape characteristics of the sand grains were found to be effective on the results. The samples with angular sand grains have higher s_u values than the samples with rounded sand grains, for all gradations employed in the present study.

中文翻译：

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砂土混合物中落锥和叶片剪切试验不排水抗剪强度结果的比较研究

本文介绍了一系列针对各种粘土-砂混合物进行的叶片剪切和落锥试验得出的一系列实验室测试结果，以了解这些方法之间的联系，这些方法通常用于确定不排水的剪切强度（s _u）。将三种不同等级（2.0–1.0 mm，1.0–0.6 mm和0.6–0.3 mm）的圆角砂和角砂与低塑性粘土以0％，10％，20％，30％，40％的比例混合，和50％。测试结果表明，从叶片剪切测试获得的s _u值始终高于从落锥测试获得的s _u值。结果表明，在混合物中使用的砂含量改变了š _ù标本参数明显。结果表明，s _u值受砂的分级特性（d ₁₀，d ₂₀，d ₃₀，d ₅₀，d ₆₀，c _u，c _c）显着影响。对于具有较大沙粒尺寸的样品，s _u值较低。最后，发现沙粒的形状特征对结果是有效的。砂粒角度较大的样品的s _u较高 对于本研究中使用的所有等级，其值均比具有圆形沙粒的样品高。