水蒸气增湿对重塑黄土抗剪强度影响的试验研究

为研究水蒸气增湿对重塑黄土抗剪强度指标的影响，以兰州市大青山地区重塑黄土为研究对象，进行不同水蒸气压力（0.05MPa、0.1MPa）下的重塑黄土高温高压水蒸气扩散柱增湿，采用快剪试验研究不同水蒸气压力增湿作用下土体抗剪强度指标的变化规律。结果表明，同一深度处，水蒸气增湿后土体的含水率沿径向减小，抗剪强度沿径向递增，水蒸气压力0.1MPa时各点处的抗剪强度均小于水蒸气压力0.05MPa时；距水蒸气扩散柱15cm处的土体含水率终将达到土体自身性质所决定的最大值，故15cm处土体的抗剪强度基本相同；同一深度处黏聚力沿径向增大，内摩擦角总体沿径向增长，但增长极小，同一点处水蒸气压力0.1MPa时的黏聚力、内摩擦均小于水蒸气压力0.05MPa时；沿深度方向，与通气点相同距离处的土体黏聚力表现出随填筑层数的增加而增加，内摩擦角没有明显差异。

Experimental study on effect of steam humidification on shear strength of remolded loess

The effect of steam humidification on the shear strength of remolded loess under different stream pressure (0.05MPa, 01MPa) in Lanzhou is studied.The variation law of shear strength index is explored. The results show that at the same depth, the moisture content of soil decreases along the radial direction and the shear strength increases along the radial direction after steam humidification. The shear strength at each point under 0.1MPa stream pressure is less than that under 0.05MPa steam pressure. The moisture content of the soil 15cm from the steam diffusion column eventually reaches the maximum value determined by the nature of the soil, so the shear strength of the soil here is basically the same. At the same depth, the cohesion is positive along the radial direction, and the internal friction angle generally increases along the radial direction, but the increase is very small. At the same point, the cohesion and internal friction under 0.1MPa steam pressure are less than that under 0.05MPa steam pressure. Along the depth direction, the cohesion of soil at the same distance from the ventilation point increases with the increase of the number of filling layers, and there is no significant difference in the internal friction angle.