李长清, 叶万军, 胡双平, 等. 2020.高富水卵砾石地层热物理参数试验研究[J].工程地质学报, 28(3): 510-519. doi: 10.13544/j.cnki.jeg.2018-382.
    引用本文: 李长清, 叶万军, 胡双平, 等. 2020.高富水卵砾石地层热物理参数试验研究[J].工程地质学报, 28(3): 510-519. doi: 10.13544/j.cnki.jeg.2018-382.
    Li Changqing, Ye Wanjun, Hu Shuangping, et al. 2020. Experimental study on thermophysical parameters of high water gravel formation for freezing construction[J]. Journal of Engineering Geology, 28(3): 510-519. doi: 10.13544/j.cnki.jeg.2018-382.
    Citation: Li Changqing, Ye Wanjun, Hu Shuangping, et al. 2020. Experimental study on thermophysical parameters of high water gravel formation for freezing construction[J]. Journal of Engineering Geology, 28(3): 510-519. doi: 10.13544/j.cnki.jeg.2018-382.

    高富水卵砾石地层热物理参数试验研究

    EXPERIMENTAL STUDY ON THERMOPHYSICAL PARAMETERS OF HIGH WATER GRAVEL FORMATION FOR FREEZING CONSTRUCTION

    • 摘要: 冻结法施工设计过程中地层的热物理参数是必须明确的指标, 为了探明高富水卵砾石地层热物理参数以及各参数与影响因素之间的相互作用关系, 本文以现场取回卵砾石样为研究对象, 通过自制试验装置测量试样起始冻结温度、比热容和导热系数, 探究含盐量对试样起始冻结温度的影响, 试样比热容、导热系数与冻结温度之间的相互作用关系, 试验结果表明:随着含盐量升高, 试样中水分的蒸气压不断下降, 造成试样需要更低的温度, 释放更多的能量才会发生冻结, 试样随着含盐量的升高起始冻结温度下降, 1、2、3号试样平均起始冻结温度从-0.46 ℃下降到-1.15 ℃; 随着冻结温度的降低试样中水分冻结, 卵砾石试样中含冰量增多, 未冻水含量减少, 由于冰的比热容是水的一半, 致使比热容不断下降, 卵砾石试样比热容从1.60 J·(g·℃)-1下降到1.06 J·(g·℃)-1; 随着冻结温度的降低试样含冰量增多, 含水量减少, 由于冰的导热系数远远大于水的导热系数, 致使卵砾石试样导热系数不断上升, 由1.71 W·(m·K)-1增加到2.13 W·(m·K)-1; 由于试样中含冰量、未冻水含量随温度不断变化, 固态和液态水的相变, 导致试样热物理性质随温度不断发生改变。

       

      Abstract: The thermophysical parameters of stratum must be clearly defined in the freezing method. This paper aims to ascertain the thermophysical parameters of water-rich gravel stratum and the interactions between the parameters and the influencing factors. It examines the effect of salt content on the initial freezing temperature of gravel samples and the interactions among freezing temperature, specific heat capacity and thermal conductivity of the samples based on their initial parameters measured by a self-made test device. The experimental results show that the increasing salt content leads to continuous decrease of the vapor pressure of water in the samples, which requires lower temperature and more energy for the samples to freeze. Specially, with the increase of salt content, the initial freezing temperature of the samples 1, 2 and 3 decreased from -0.46 to -1.15 ℃. With the decrease of freezing temperature, the ice content in the samples increased while the unfrozen water content decreased. Because the specific heat capacity of ice is half of that of water, the specific heat capacity of the samples decreased continuously from 1.60 J·(g·℃)-1 to 1.06 J·(g·℃)-1. Because the thermal conductivity of ice is much larger than that of water, the thermal conductivity of the samples increased from 1.71 W·(m·K)-1 to 2.13 W·(m·K)-1. As the ice content and unfrozen water content in the samples changed with temperature, the liquid-solid phase transformation of the water caused the variation in physical and mechanical properties of the samples.

       

    /

    返回文章
    返回