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土料压缩特性参数是计算地基沉降变形的重要指标。为明确砂泥岩混合填料在不同浸水时间下压缩特性,设置7组不同时间的浸水方案、2种浸水方式,采用侧限压缩试验探究砂泥岩填料经不同时间浸水后的强度变化规律。试验结果表明,与不浸水试样相比,砂泥岩混合料浸水1 h后轴向变形增大11.48%,浸水5 d后,压缩模量降低了31.22%,压缩系数增大了45.03%;浸水5 d后,轴向变形比浸水1 h增大了47.40%,孔隙比减小了7.71%。长时间浸水降低砂泥岩混合料压缩模量,增大其压缩系数,其压缩变形增大。建议将压缩系数、压缩指数与压缩模量相结合来评判砂泥岩混合料长期浸水条件下的压缩特性。不同浸水时间下的应力应变曲线在lnε-ln p平面内呈直线,曲线簇呈扫帚状且有汇聚趋势。浸水饱和与真空抽气饱和的试验数据差值小于5%,这两种饱和试验方法对砂泥岩混合料压缩特性的影响不明显。
Soil compression characteristics of parameters is an important indicator of settlement calculation. In order to clarify the compression characteristics of sand-shale mixed fillers under different immersion time, seven groups of immersion schemes and two kinds of immersion schemes were set up at different times, and the lateral compressive tests were used to investigate the strength variation of sand-limestone fillers after immersion for different periods. The experimental results show that the axial deformation of sand-shale mixture increases by 11.48% after immersed for 1 h and decreases by 31.22% and 45.03% after water immersion for 5 days, After 5 d, the axial deformation increased by 47.40% and the void ratio decreased by 7.71% 1 h after immersion in water. Water immersion for a long time reduces the compressive modulus of sand-shale mixture, increases its compressibility and increases its compressive deformation. It is suggested that the compressibility, compressibility index and compressive modulus are combined to evaluate the compressive properties of sand-shale mixture under long-term immersion conditions. The stress-strain curve under different immersion time showed a straight line in the lnε-ln p plane, and the curve cluster showed a broom-like shape with a tendency of convergence. Difference between the test data of saturated water saturation and vacuum suction saturation is less than 5%. The effect of these two saturation test methods on the compression characteristics of sand-shale mixture is not obvious.