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基于混合料温度计算公式,计算了预冷各种原材料对混凝土的降温效果,确定了符合目标入仓温度要求的原材料冷却方案。在16℃入仓温度条件下,对大体积混凝土进行了Midas有限元模拟,分析了不同仓层厚度、不同冷却水管布置参数对温度峰值和温度场的影响。原材料降温计算结果显示,预冷骨料降温1℃时混凝土降温0.77℃,耗能1 823 kJ,制冷水降温1℃,混凝土降温0.18℃,耗能419 kJ。温度场模拟结果显示,仓层厚度为3.0 m时,混凝土温度峰值最大,不布置冷却水管时为46.4℃,布置单层冷却水管(水管距离1.5 m)时为42.3℃。当冷却水管垂直间距减小至1.0 m时,温度峰值为40.0℃,水平距离减小至1.0 m时温度峰值为41.5℃,水管层数增加后,温度峰值区范围明显减小。结果表明,骨料降温至10℃,制冷水降温至4℃,可在全年实现入仓温度不超过16℃。混凝土内温度峰值随仓层厚度减小略有减小,但整体降幅较小,合理仓层厚度在2.5~3.0 m。减小仓层厚度和布置冷却水管的降温效果是线性叠加的。水管间距、层数对温度峰值影响较小,但可明显影响温度峰值区的范围。最优温控方案为:浇筑仓层厚度3.0 m,设置两层冷却水管,水平间距1.5 m,垂直间距1.0 m。
Abstract:Based on the formula of mixture temperature, the cooling effect of various raw materials on concrete was calculated, and the cooling scheme of raw materials meeting the requirements of target inlet temperature was determined. When the inlet temperature was 16 ℃, finite element simulation by Midas was carried out, and the influence of different thickness of concrete layer and different layout parameters of cooling water pipe on peak temperature and temperature field was analyzed.The calculation result showed that when the pre-cooled aggregate drops 1 ℃, the concrete drops 0.77 ℃, and the energy consumption was 1 823 kJ; the cooling water temperature drops 1 ℃, the concrete drops 0.18 ℃, and the energy consumption was 419 kJ. The simulation result of temperature field showed the peak value of concrete temperature is maximum when the layer thickness is 3.0 m. The temperature is 46.4 ℃ when no cooling water pipes are deployed, and 42.3 ℃ when single-layer cooling water pipes are deployed(water pipes are 1.5 m away). When the vertical distance of cooling water pipes is reduced to 1.0 m, the peak temperature is 40.0 ℃, and 41.5 ℃when the horizontal distance is 1.0 m. When the number of water pipe layers is increased, the peak temperature range decreases significantly. The result show that when the aggregate is cooled to 10 ℃ and the cooling water to 4 ℃, the inlet temperature will not exceed 16 ℃ in the whole year. The peak temperature inside the concrete decreases slightly with the decrease of the thickness of layer, but the decrease is small, so the reasonable thickness of layer is 2.5~3.0 m. The cooling effect of reducing the thickness of layer and cooling water pipe is linear superposition. The water pipe distance and the number of pipe layers have little effect on the peak temperature, but can obviously affect the range of the peak temperature region. The optimal temperature control scheme is as follows: the thickness of layer is 3.0 m, and two layers of cooling water pipes are set with a horizontal spacing of 1.5 m and a vertical spacing of 1.0 m.
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基本信息:
DOI:10.13928/j.cnki.wrahe.2024.S1.021
中图分类号:TV544
引用信息:
[1]许后磊,舒德伟,唐季,等.大体积混凝土入仓温度控制及水管冷却优化技术研究[J].水利水电技术(中英文),2024,55(S1):144-150.DOI:10.13928/j.cnki.wrahe.2024.S1.021.
基金信息:
国家自然科学基金(52379124); 国家重点研发计划(2021YFB2600200); 云南省科技攻关计划“云南省水网空间规划与智慧水网关键技术研究”(202203AA080010),“智慧水电工程安全运行关键技术与集成示范”(202203AA080009)