基于室内实验和现场温度监测资料,提出适合于高掺粉煤灰混凝土的绝热温升组合函数模型。利用这一模型对某拱坝混凝土绝热温升进行反演,结果表明,对于高掺粉煤灰混凝土,组合函数模型能更好地反映其实际发热过程,特别是封拱后的发热过程,拟合精度均优于其他绝热温升模型。利用该模型反馈分析了后期温度回升对拱坝成拱后整体应力分布的影响,结果表明,在初次蓄水期和长期运行期,封拱后的温度回升会在坝体局部产生不利影响,应引起重视。
This paper develops an adiabatic heat combined function model of high content fly-ash concrete based on laboratory tests and in-situ monitoring data. Using this model, a back analysis on the adiabatic heat parameters of concrete for an arch dam is conducted. Results show that the model can better simulate the actual heating process, particularly the one after closure grouting, and its fitting accuracy is higher than other models. An analysis on the negative impacts of temperature rise on the overall stress distribution of arch dam reveals that temperature rise after closure can deteriorate the local stress in the periods of initial impoundment and long-term operation, to which more attention should be paid.