丁法龙, 茅泽育. 寒区水塘冰温度应力原型观测及分析[J]. 工程力学, 2021, 38(9): 239-245, 256. DOI: 10.6052/j.issn.1000-4750.2020.09.0624
引用本文: 丁法龙, 茅泽育. 寒区水塘冰温度应力原型观测及分析[J]. 工程力学, 2021, 38(9): 239-245, 256. DOI: 10.6052/j.issn.1000-4750.2020.09.0624
DING Fa-long, MAO Ze-yu. STUDY ON THERMAL ICE STRESSES OF A POND IN COLD REGION[J]. Engineering Mechanics, 2021, 38(9): 239-245, 256. DOI: 10.6052/j.issn.1000-4750.2020.09.0624
Citation: DING Fa-long, MAO Ze-yu. STUDY ON THERMAL ICE STRESSES OF A POND IN COLD REGION[J]. Engineering Mechanics, 2021, 38(9): 239-245, 256. DOI: 10.6052/j.issn.1000-4750.2020.09.0624

寒区水塘冰温度应力原型观测及分析

STUDY ON THERMAL ICE STRESSES OF A POND IN COLD REGION

  • 摘要: 冰体内温度应力引起的膨胀压力可导致结构物不同程度的破坏,其值是寒区水工建筑物的关键设计参数。为探究静冰温度应力的时空分布特性,采用原型观测研究手段,结合理论分析及计算,以黑龙江省大庆市青花湖6号水塘为研究对象,对水塘淡水冰层内部温度场和应力场进行了观测及分析。结果表明:冰温变化主要取决于上部气温的波动情况,表层冰温与气温呈良好的线性关系,且斜率在0.38~0.56;深度30 cm以上的冰温对气温变化的响应较为敏感,30 cm以下的冰温沿垂向基本呈线性分布;基于冰的Bergdahl粘弹性本构关系提出了一种冰温度应力计算模型,并结合实测数据回归分析确定模型中的参数,参数的拟合值明显依赖于测点位置;温度应力模型计算结果与观测结果吻合良好;从距离侧边挡墙较远的测点1到较近的测点4,随着周边围岸约束作用的增强,整体冰应力水平呈递增趋势;冰应力沿垂向呈非单调分布,即冰层表面产生的应力稍小,最大应力值出现在冰深10 cm~30 cm处,其下随深度逐渐减小,且冰应力只在0.7 m以内的冰层上部产生。

     

    Abstract: Static ice pressure due to thermal expansion is a key parameter for the design of hydraulic structures in cold regions. Thermal ice stress is affected by various factors, including thermal conditions of ice sheet (ice temperature, temperature rise rate, etc.), ice sheet constraint conditions, ice sheet thickness, etc., which leads to uncertainties in the estimation of thermal ice stress. To investigate the spatial and temporal distribution of thermal ice stress, a prototype observation was conducted to No.6 pond of Qinghuahu lake in Daqing City, Heilongjiang Province, and the ice temperature and thermal stress were fully analyzed. The analysis results indicate that ice temperature mainly depends on the fluctuation of air temperature, and that the ice temperature of each layer fluctuates more gently with time than air temperature. With the increase of ice depth, the fluctuation range of ice temperature decreases, and ice temperature increases. The surface ice temperature is well linearly related with air temperature by the change rate between 0.38 and 0.56, and the influence of air temperature on ice temperature is quite obvious within 30 cm, and ice temperature below 30 cm presents a linear distribution along depth. Based on Bergdahl's rheological constitutive relation of static ice, a mathematical model of thermal ice stress is proposed. The undetermined parameter in the model is determined by regression combining with measured data, and its values obviously depend on measuring positions. The calculated values of ice stress agree well with the measured ones. From station 1 to station 4, the overall thermal ice stresses increase. The stress is non-monotonically distributed along ice depth, i.e., thermal stress in surface ice is slightly smaller, reaches a maximum at the depth of 10~30 cm, and then gradually declines with depth. Moreover, thermal ice stresses only appear on the upper part of the ice within 0.7 m.

     

/

返回文章
返回