| 摘要: |
| 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ln ε-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。 |
| 关键词: 浸水时间 压缩特性 砂泥岩混合料 |
| DOI： |
| 分类号:TV41 |
| 基金项目:重庆市研究生科研创新项目(CYB15109); 重庆交通大学大学生创新创业训练计划项目(201510618021); 重庆交通大学国家内河航道整治工程技术研究中心暨水利水运工程教育部重点实验室开放基金资助项目(SLK2014B07) |
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| Influences of soaking time on compression properties of sandstone-mudstone mixture |
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JIAN Fu-xian, ZHANG Hong-wei, ZHANG Jun-tang, YOU Ke-qin
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College of River and Ocean Engineering, Chongqing Jiaotong University, Chongqing
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| Abstract: |
| The compression properties of soil aggregates are an important reference index in the process of calculating settlement and deformation of some foundations. In order to understand the compression properties of the sandstone-mudstone mixture treated for different soaking times, 7 different soaking time plans and 2 different saturation ways are set up in this paper. A confining compression test method is adopted to finish the exploration that how the soil aggregate’ intensity changes when the sandstone-mudstone mixture is soaked for different times. The experimental analysis results show that, comparing with the data without immersed specimens, the axial deformation increased by 11.48% after 1 h of the soaking time in the experimental scheme. And the compression modulus decreased by 31.22% and the compression coefficients increased by 45.03% after 5 d of the soaking time. Further, comparing the test results of the soaking time in 1 h, the axial deformation increased by 47.40% and the void ratio decreased by 7.71% after 5 d of the soaking time. Thus, the compression modulus was reduced, the compression coefficients increased, and the deformation increased along with the soaking time prolonged for the soil aggregates. The analysis above suggests that the compression modulus, the compression coefficients and the compression index should be combined to evaluate the sandstone-mudstone compression properties under the conditions of long-term immersion. And it also suggests that the compression coefficients should not be separated from each other to evaluate them. In addition, it is found from analysis of data under different soaking times that the stress-strain curves present a series of straight lines when they are in the lnε-ln p coordinate. These lines show a shape of broom-part and also have a convergence trend in that coordinate. The difference of test data is within 5% between the vacuum way and the immersed way. Thus as a result, the two saturation ways have no significant influences on the compression properties of the sandstone-mudstone mixture. |
| Key words: soaking time compression property sandstone-mudstone mixture |
