A critical state testing round robin programme was carried out on sandy silt gold tailings. This involved 15 laboratories around the world testing a sandy silt tailings to infer its critical state line (CSL). Methods to be used were intentionally not supplied to participants, to enable the current methods being employed in industry and academia to be obtained in an unbiased manner. All but one of the laboratories involved in the study used the moist tamping sample preparation technique, generally to produce loose, contractive specimens. Void ratio was measured using a variety of means, including cell calibration, end-of-test water content and end-of-test soil freezing (EOTSF) to assist in measuring the final water content. Of the 15 entries, four were excluded from the primary comparison owing to various issues that appear to have led to their divergence from most of the entries received. Of the remaining entries, the best reproducibility was produced by laboratories that used EOTSF to measure void ratio. Most other test procedure variations appeared to have a negligible effect, with the exception of fixing of the top platen and possibly sample size. A CSL elevation range of 0·04 void ratio for laboratories using EOTSF was observed.

中文翻译：

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临界状态线测试循环程序的结果

对砂质粉砂金尾矿进行了临界状态测试循环程序。这涉及全球 15 个实验室测试含砂淤泥尾矿以推断其临界状态线 (CSL)。有意不向参与者提供要使用的方法，以便能够以公正的方式获得工业和学术界目前采用的方法。除了参与研究的实验室之一外，所有实验室都使用湿夯样品制备技术，通常用于生产松散、收缩的样品。空隙率是使用多种方法测量的，包括单元校准、试验结束含水量和试验结束土壤冻结 (EOTSF)，以帮助测量最终含水量。在这 15 个条目中，四个被排除在主要比较之外，原因是似乎导致它们与大多数收到的条目存在分歧的各种问题。在其余条目中，最佳再现性是由使用 EOTSF 测量空隙率的实验室产生的。大多数其他测试程序变化似乎具有可忽略不计的影响，除了顶部压板的固定和可能的样本大小。观察到使用 EOTSF 的实验室的 CSL 升高范围为 0·04 空隙率。