| 引用本文: | 肖勇涛,何育才,陆立志,等.混凝土面板堆石坝施工期面板温度应力及控制措施研究[J].灌溉排水学报,2025,44(11):38-46. |
| XIAO Yongtao,HE Yucai,LU Lizhi,et al.混凝土面板堆石坝施工期面板温度应力及控制措施研究[J].灌溉排水学报,2025,44(11):38-46. |
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| 摘要: |
| 【目的】研究混凝土堆石坝施工期面板的底部约束和内外温差对面板温度应力的影响。【方法】依托开化水库工程，运用有限元模型对不同计算时段和计算方案下面板的温度和温度应力进行了数值仿真，并提出了施工期面板温度应力控制措施。【结果】底部约束对面板表面温度应力影响较大，摩擦系数存在临界值；在底部约束一定的条件下，内外温差是产生面板表面温度应力的主要因素，施加养护毯措施可明显降低内外温差和表面温度应力；表面温度应力在面板中下部达到最大；寒潮条件下面板设计温度应力不超过允许抗拉强度；施工期所有长面板浇筑温度均小于允许浇筑温度。【结论】开化水库施工过程中控制面板底部摩擦系数小于临界值，面板施工后及时施加养护毯措施，能有效避免面板出现裂缝。 |
| 关键词: 面板；底部约束；内外温差；温度应力控制措施；允许浇筑温度；开化水库 |
| DOI：10.13522/j.cnki.ggps.2025018 |
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| Thermal stress and control measures in concrete-face rockfill dam construction |
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XIAO Yongtao, HE Yucai, LU Lizhi, LIU Shoujun, SU Jiexun, LI Yu, YAN Fanxin
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1. South to North Water Diversion (Kaihua) Water Service Co., Ltd, Quzhou 324300, China;
2. China South to North Water Diversion Group Water Network Water Investment Co., Ltd, Beijing 100071, China
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| Abstract: |
| 【Objective】Controlling surface thermal stress during the construction of concrete-face rockfill dams (CFRDs) is critical for preventing early cracking in the face slabs. This study investigates the effects of bottom constraints and internal-external temperature differences on thermal stress in CFRDs during their construction.【Method】Based on the Kaihua Reservoir project, a finite element model was developed to simulate temperature distribution and thermal stress of the face slab during different construction periods and schemes. The spatial distribution of surface thermal stress and allowable concreting temperatures were analyzed, from which we evaluated the effectiveness of various control measures in mitigating thermal stress.【Result】Bottom constraints significantly influenced surface thermal stress, with a critical friction coefficient of 0.6. The roller-compacted mortar slope protection method implemented at Kaihua Reservoir ensured that the bottom friction coefficient remained below this critical value, highlighting the importance of construction quality. Under fixed bottom constraints, the temperature difference between the inside and outside of the face slab was the primary factor driving surface thermal stress. Greater internal-external temperature differences led to higher thermal stress, whereas applying maintenance blankets could effectively reduce both temperature differences and stress levels. Thinner face slabs exhibited smaller internal-external temperature differences. Maximum surface thermal stress occurred in the middle to lower sections of the slab, approximately 28-52 meters from the toe board. Under cold wave conditions, the design thermal stress of the face slab remained below the allowable tensile strength.【Conclusion】We propose an allowable concreting temperature for the Kaihua Reservoir face slab. Comparisons show that the results of the proposed method are consistent with on-site measurements, and that its actual temperatures remained below the critical threshold. Ensuring a bottom friction coefficient below the critical value and timely application of maintenance blankets after face slab construction can effectively prevent cracking of the CFRD face slabs. Our results provide design guidance for thermal stress control during construction of concrete-face rockfill dams. |
| Key words: face slab; bottom constraint; temperature difference between inside and outside; thermal stress control measures; allowable concreting temperature; Kaihua Reservoir |
