This paper demonstrates the results of a long-term study on the effect of water saturation on the mechanical properties and failure modes of tuffs and andesites. As an initial step, an extensive literature survey has been performed about the water effect on mechanical strength of rocks. Afterwards, experimental studies have been initiated and five different igneous rock samples (three tuffs and two andesites) were subjected to uniaxial compressive strength, indirect tensile strength, ultrasonic pulse velocity tests under three extreme conditions which are fully saturated, oven-dry and air-dry. Additionally, mass gain or loss of representative samples was tracked for 1-year period and the wetting and drying profiles of the rocks were demonstrated. Effect of the water saturation and natural moisture on the compressive strength, tensile strength, ultrasonic pulse velocity and failure modes of the samples was investigated. Consequently, it has been seen that while compressive and tensile strength of the samples were reduced with the presence of water and natural moisture, ultrasonic pulse velocities have been increased with water saturation. Additionally, andesite samples demonstrated a shear localization during the uniaxial compression due to saturation.

中文翻译：

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一些火成岩的长期润湿特征和饱和诱导强度降低

本文展示了一项长期研究的结果，研究结果表明饱和水对凝灰岩和安山岩的力学性能和破坏模式的影响。作为第一步，已经进行了有关水对岩石机械强度的影响的广泛文献调查。之后，已开始进行实验研究，并在三种极端条件下对五个不同的火成岩样品（三个凝灰岩和两个安山岩）进行了单轴抗压强度，间接抗拉强度，超声脉冲速度测试，测试条件为完全饱和，烘箱干燥和空气干燥。干。此外，在1年的时间内跟踪了代表性样品的质量增加或损失，并证明了岩石的润湿和干燥曲线。水分饱和度和天然水分对抗压强度，抗张强度，研究了样品的超声脉冲速度和破坏模式。因此，已经看到，尽管在存在水和天然水分的情况下样品的抗压强度和拉伸强度降低，但是随着水饱和度的增加超声脉冲速度已经提高。此外，安山岩样品在单轴压缩过程中由于饱和而表现出剪切局部化。