Shear strength (fall cone) from IODP Hole 386-M0094A

Undrained shear strength data from fall cone testing of the above given hole of International Ocean Discovery Program (IODP) Expedition 386 (Japan Trench Paleoseismology). This dataset was obtained at the end of the core processing workflow during the third phase (Personal Sampling Party, PSP) of expedition 386, which took place between 2022-11-15 – 2022-11-30 onboard D/V Chikyu. Measurements were performed on the work halves of core sections at an interval of approx. 1 meter using an ELE International fall cone penetrometer (STANDARD BS1377) with the following cone specifications: 35 mm cone, 30 degrees angle, around 30 g, stainless steel, 3.25 (+/-0.05) mm rod diameter. The fall cone penetrometer measures the penetration of a cone as it free falls and embeds itself in the sediment. During testing, the cone (pointing downward) was lowered, so that it just touched the surface of the split core before it was locked in place with the dial gauge reading noted. Undrained shear strength was determined using the empirical formula determined by Hansbo (1957, http://urn.kb.se/resolve?urn=urn:nbn:se:swedgeo:diva-356). The formula of Hansbo (1957) may be inadequate for silty sediment (present in some Expedition 386 cores); therefore, fall cone measurements were obtained preferably in clay-dominated intervals. In three cases (386-M0081B-1H-21,25.5; 386-M0088D-1H-7,25.5; 386-M0091B-1H-10,25.5), data collection was not successful for different reasons (IT problems, human failure). For the sake of completeness, however, the \"Sample labels\" were nevertheless noted and results left empty. […]本数据集包含国际大洋发现计划（International Ocean Discovery Program, IODP）386航次（日本海沟古地震学研究）指定钻孔的落锥试验（fall cone testing）不排水抗剪强度（undrained shear strength）数据。该数据集采集于386航次第三阶段（个人采样队，Personal Sampling Party, PSP）岩芯处理流程的末期，此阶段航次于2022年11月15日至2022年11月30日在"地球号"（D/V Chikyu）钻探船上开展。测试以约1米的间隔对岩芯剖开后的工作半片进行，采用符合BS1377标准的ELE International落锥贯入仪（fall cone penetrometer，型号：STANDARD BS1377），其锥头参数如下：直径35 mm、锥角30°、质量约30 g、材质为不锈钢，杆径为3.25（±0.05）mm。落锥贯入仪通过记录锥头自由下落并嵌入沉积物时的贯入深度来获取测试数据。试验过程中，朝下的锥头被缓缓下放，直至刚好接触剖开岩芯的表面，随后固定位置并记录百分表读数。不排水抗剪强度通过Hansbo（1957）提出的经验公式计算得到，公式来源链接：http://urn.kb.se/resolve?urn=urn:nbn:se:swedgeo:diva-356。由于Hansbo（1957）提出的公式对粉砂质沉积物的适用性有限，而部分386航次的岩芯中存在此类沉积物，因此试验优先在以黏土为主的层位开展落锥测试。共有3组测试数据采集失败，对应样品编号分别为386-M0081B-1H-21,25.5、386-M0088D-1H-7,25.5及386-M0091B-1H-10,25.5，失败原因包括信息技术故障及人为操作失误。但为保证数据完整性，仍记录了对应样品标签，且未填写测试结果。……