Large flexible calibration chambers (CCs) to evaluate and develop interpretation methods for cone penetration tests (CPTs) in cohesionless soils have been used since the late 1960s. Nevertheless, only average boundary stress values are known in almost all tests already performed. Tactile pressure sensors (TPS) represent a useful tool to assess the stress distribution in an area under loading and have been applied in some geotechnical studies. This study presents the results of CPTs carried out on a large flexible CC in a very loose and a medium-dense fine quartz sand. TPS were placed on the walls of the CC, allowing the measurement of horizontal stresses and their spatial distribution in all test phases: sample formation, lateral and cavity cell filling, piston filling, sample stressing and CPT. In particular, TPS were able to measure the horizontal stresses before the cavity and lateral cell filling – that is, when no information is available about the horizontal stresses in regular tests. The measurements contribute to the discussion on the influence of the CC boundaries on the test results. The results encourage the use of TPS on a more routine basis in large flexible CC testing.

中文翻译：

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使用触觉传感器在大型校准室上进行水平应力测量

自 20 世纪 60 年代末以来，人们一直在使用大型灵活校准室 (CC) 来评估和开发无粘性土壤中锥入度试验 (CPT) 的解释方法。然而，在几乎所有已进行的测试中，仅已知平均边界应力值。触觉压力传感器 (TPS) 是评估负载区域应力分布的有用工具，并已应用于一些岩土工程研究中。本研究介绍了在非常松散和中等致密的细石英砂中的大型柔性 CC 上进行 CPT 的结果。TPS 放置在 CC 的壁上，可以测量所有测试阶段的水平应力及其空间分布：样品形成、横向和空腔单元填充、活塞填充、样品应力和 CPT。特别是，TPS 能够在空腔和横向单元填充之前测量水平应力，即在常规测试中无法获得有关水平应力的信息时。这些测量有助于讨论 CC 边界对测试结果的影响。结果鼓励在大型灵活 CC 测试中更常规地使用 TPS。