重塑Q3黄土K0三轴蠕变特性的试验研究

目的]研究陕西省延安地区重塑Q_3黄土高填方工程的后期沉降变形特性,为高填方工程的设计、施工提供一定的技术和理论支撑。方法]通过改进K0三轴蠕变仪,对所取黄土进行了不同压实度、不同含水量、不同竖向应力下的室内土的静止侧压力系数K_0三轴固结排水蠕变试验。结果]重塑Q_3黄土具有明显的蠕变特性,在低应力条件下,呈现出典型的衰减蠕变;在K_0条件下,随着含水量增大、竖向应力的增大,压实度的减小,蠕变呈增强趋势,蠕变变形量增大;在低水平应力的条件下,土体所受侧向应力与竖向应力成线性关系。结论]建立了重塑Q_3黄土关于竖向应力的自定义蠕变模型,通过试验数据拟合获得了模型参数,所建模型能很好地描述延安地区重塑Q_3黄土的蠕变特性。

Experimental Study on K0 Triaxial Creep Properties of Remolded Q3 Loess

Objective] To analyze the late settlement of high filled project in Yan''an District of Shaanxi Province in order to provide technological and theoretic support for the design and construction of high filled project.Methods] A variety of laboratory consolidated drained static lateral pressure coefficient K₀ triaxial creep tests were conducted under different water content, compacted degree and vertical stress by using a refitted K₀ triaxial creepmeter.Results] The remolded Q₃ loess had an obvious creep properties, and it showed a typical attenuation creep under low stress level. Creep phenomenon showed an increase trend and the deformation of creep enlarged, with higher water content, higher pressure stress and smaller compacted degree. Under low stress level, there was a linear relationship between lateral stress and vertical stress.Conclusion] Based on the tested data, a user-defined creep model of remolded Q₃ loess about vertical stress was established, and characteristic parameters were obtained by fitting test data. The established model can well describe the properties of remolded Q₃ loess in Yan''an District.