为研究冻结竖井施工中地下水渗流对冻结温度场时空演化规律的影响，以淮北煤田临涣矿区袁店二矿为工程背景，根据现场实测数据及水热耦合数值模拟计算结果分析现场砂土渗透地层温度场的时空演化规律；
通过控制变量法，研究流速、冻结管间距、冻结管直径及盐水温度对温度场的影响； 结合灰色关联度理论对冻结温度场进行敏感性分析。研究结果表明： 1)冻结竖井施工中，开挖及筑壁带来的施工热扰动对井帮处冻结壁的形成有削弱作用，地下水渗流使得冻结管布置圈径外侧上下游温度相差2~4 ℃。2)通过数值计算结果与现场实测数据的对比验证，证实将SFCC(soil freezing characteristic curve)离散试验数据公式化并嵌入数值计算软件中，能够可靠地模拟埋深135 m富水砂层的温度场演化过程。3)富水砂层在冻结30 d时冻结壁交圈，冻结100 d时冻结壁有效厚度可达5 m以上，且渗流方向上的冻结温度场分布和上下游冻结壁温度变化具有明显差异。4)单因素作用下，冻结管直径与盐水温度的变化对上游冻结壁厚度及非对称系数的影响较小，变化幅度均不超过10%； 而冻结管间距的改变对交圈时间影响显著，变化幅度超过60%。5)流速小于5 m/d时，交圈时间对盐水温度最为敏感，上游冻结壁厚度和冻结壁非对称系数对冻结管间距最为敏感；
流速大于5 m/d时，交圈时间和冻结壁非对称系数受流速影响最为显著，上游冻结壁厚度受冻结管间距影响最为显著。
The authors examine the
influence of groundwater seepage on the spatio-temporal evolution of the freezing temperature field during frozen
shaft construction. Using field-measured data and
hydrothermally coupled numerical simulations from the Yuandian No. 2 coal mine
in the Linhuan mining area of the Huaibei coalfield, Anhui, China, they analyze
the spatio-temporal evolution in a sand-permeated formation. Control variable method is employed to examine
the effects of key parameters, including flow rate, freezing pipe spacing,
freezing pipe diameter, and brine temperature, on the temperature field.
Furthermore, a sensitivity analysis of the freezing temperature field is
conducted using gray correlation theory to quantify the influence of each
parameter. The key findings are summarized as follows: (1) During freezing
shaft construction, thermal disturbances caused by excavation and wall
construction significantly weaken the formation of the freezing wall along the
shaft side. Groundwater seepage creates a temperature gradient of 2 ℃－4 ℃ between the upstream and downstream
regions outside the freezing pipe arrangement circle. (2) Comparative analysis
between numerical simulations and field-measured data
confirms that incorporating soil freezing characteristic curve discrete test
data into the numerical software reliably reproduces the evolution of the
temperature field in the water-rich sand layer at a
depth of 135 m. (3) In the water-rich sand layer, the
freezing wall achieves closure after 30 days of freezing, with its effective
thickness exceeding 5 m by the 100th day. Notably, the temperature field along
the seepage exhibits significant heterogeneity, with pronounced differences in
temperature variations between the upstream and downstream sections of the
freezing wall. (4) Under singlefactor conditions,
variations in freezing pipe diameter and brine temperature affect the thickness
and asymmetry coefficient of the upstream freezing wall, with changes remaining
under 10%. However, alterations in freezing pipe spacing significantly impact
closure time, demonstrating a variation range exceeding 60%. (5) For flow rates
below 5 m/d, brine temperature has the greatest influence on closure time,
while freezing pipe spacing plays a key role in determining the thickness and
asymmetry coefficient of the upstream freezing wall. At flow rates exceeding 5
m/d, both closure time and the asymmetry coefficient are predominantly
influenced by flow rate, whereas freezing pipe spacing continues to have the
largest effect on wall thickness.
