李宏俊 潘少红 杨建桥

摘 要：结合公路路基对泥质软岩填料的实际应用需求，考察了泥质软岩填料的击实、承载比、直剪和固化性能。结果表明，当P5分别为50%、70%和90%时，泥质软岩填料的最佳含水率分别为9.86%、9.20%和8.74%，对应的最大干密度分别为1.984g/cm3、2.144g/cm3和2.177g/cm3，击实后P5为50%、70%和90%的试件的不均匀系数分别增加至26.26、22.11和21.32，级配明显改善;压实度分别为93%、94%和96%的试件的承载比平均值分别为12.1%、18.2%和25.3%;在相同的垂直压力下，压实度更大的泥质软岩填料试件的剪切强度会更大。当轴向应力分别为200kPa、400kPa和800kPa时，浸水后泥质软岩填料试件的湿化变形率分别为1.96%、2.67%和3.00%;浸水后泥质软岩填料试件的湿化变形率会随着轴向压力增加而增大，但是压实度为93%时浸水后泥质软岩填料试件的湿化变形率整体不高。

关键词：公路路基;泥质软岩填料;承载比;直剪;固化

中图分类号：U416.1                           文献标识码：A                        文章编号：1001-5922（2021）07-0058-05

Study on Mechanical Characteristics of Soft Rock Filling in Highway Subgrade

Li Hongjun， Pan Shaohong， Yang Jianqiao

（Yunnan Land and Resources Vocational College， Kunming 652501， China）

Abstract：The coMPaction， load bearing ratio， direct shear and curing properties of the argillite soft rock fillers were investigated according to the practical application requirements of the highway subgrade for argillaceous soft rock filler. The results show that when P5 is 50%， 70% and 90%， the optimal moisture content of the argillaceous soft rock filler is 9.86%， 9.20% and 8.74%， and the corresponding maximum dry density is 1.984g/cm3， 2.144g/cm3 and 2.177g/cm3， respectively. After coMPaction， the non-uniformity coefficient of the specimens with P5 being 50%， 70% and 90% increases to 26.26， 22.11 and 21.32， and the grading is significantly improved. The average load bearing ratios of the specimens with the coMPaction density of 93%， 94% and 96% were 12.1%， 18.2% and 25.3%， respectively. Under the same vertical pressure， the shear strength of argillaceous soft rock packing specimens with higher coMPacted density will be greater. When the axial stress was 200kPa， 400kPa and 800kPa respectively， the wet deformation rates of muddy soft rock packing specimens after immersion were 1.96%， 2.67% and 3.00% respectively. The wet deformation rate of muddy soft rock packing specimen increases with the increase of axial pressure， but the wet deformation rate of the argillaceous soft rock filler specimen after immersion in water is not high overall when the coMPaction density is 93%.

Key words：highway roadbed; argillaceous soft rock filler; bearing ratio; direct shear; solidification

泥质软岩在我国西南和西北地区有广泛分布，在公路建设极大推广的应用背景下，如何将泥质软岩作为填料使用来解决目前填料匮乏的现状[1]，不仅可以降低公路路基建设成本，还可以减少对耕地等资源的占用，是非常值得研究的课题[2-3]。虽然将泥质软岩应用在公路路基中具有较好的社会效益、经济效益和环境效益，但是实际应用过程中由于泥质软岩的强度较低以及风化程度较高等缺陷，容易在完工后造成路基沉降以及开裂等现象[4-7]，因此，需要对泥质軟岩的力学特性进行研究，包括击实特性、剪切强度和压缩固结特性等，结果将有助于泥质软岩在公路路基工程中的广泛应用，并具有重要的现实意义。……