Abstract The railway embankment applied to high-speed railways is required to have high performance in terms of strength and deformation characteristics. Especially in the case of railway embankments that support slab tracks, the allowable settlement is very small. There are two technical challenges in constructing high-speed rail embankments to support slab tracks in India. The first challenge is dealing with problematic black cotton soil (BCS), which is widely distributed in India but very unusual soil in Japan. The second challenge is posed by the strict deformation requirement in the construction of the embankments. In this study, a 6 m-high test embankment was constructed on BCS in India. The deformation of the embankment and changes in water content were measured over a period of 18 months. In the construction of the test embankment, two different BCS countermeasures were applied. The results of the tests on this embankment were compared with those from an embankment without countermeasures. Complicated deformation behaviors, including settlement and the uplift of embankment, were observed in the section without countermeasure. However, in the embankment with cement-mixed gravelly soil (CGS) slab improvement with geosynthetics, the much lower amplitude of embankment deformation is evidence of the effectiveness of this countermeasure. The cohesive non-swelling soil (CNS) layer applied immediately below the embankment to reduce the water content fluctuation of BCS was not effective enough for use for high-speed railway embankment. Besides determining the technical challenges for the BCS countermeasures, the results of this study confirmed that a high-performance embankment can be constructed with Indian embankment material by performing sufficient compaction management.

中文翻译：

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印度膨胀土“黑棉土”高铁试验路堤施工及现场测量

摘要 应用于高速铁路的铁路路基要求具有较高的强度和变形特性。特别是在支撑板式轨道的铁路路堤的情况下，允许沉降非常小。在印度，建造高速铁路路堤以支撑板式轨道存在两个技术挑战。第一个挑战是处理有问题的黑棉土 (BCS)，这种土在印度广泛分布，但在日本非常不寻常。第二个挑战是路堤施工中严格的变形要求。在这项研究中，在印度的 BCS 上建造了 6 m 高的测试路堤。在 18 个月的时间里测量了路堤的变形和含水量的变化。在试验路堤的建设中，应用了两种不同的 BCS 对策。将该路堤的测试结果与未采取对策的路堤的测试结果进行了比较。在未采取措施的路段观察到路堤沉降和抬升等复杂变形行为。然而，在用土工合成材料改良水泥混合碎石土 (CGS) 板的路堤中，路堤变形幅度低得多是该对策有效性的证据。紧贴在路堤下方以减少 BCS 含水量波动的粘性非膨胀土 (CNS) 层对于高速铁路路堤的使用效果不佳。除了确定 BCS 对策的技术挑战外，