考虑分层填充的非均质堆石混凝土温度研究  

Study on temperature of heterogeneous rock-filled concrete considering layered filling process

作　　者：徐小蓉 肖安瑞[1] 梁婷 金峰 余舜尧[3] 邱流潮 XU Xiaorong;XIAO Anrui;LIANG Ting;JIN Feng;YU Shunyao;QIU Liuchao(School of Water Resources and Hydropower Engineering,North China Electric Power University,Beijing 102206,China;State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China;Astronautics Times Feihong Technology Company Limited,Beijing 100094,China;College of Water Resources&Civil Engineering,China Agricultural University,Beijing 100083,China)

机构地区：[1]华北电力大学水利与水电工程学院,北京102206 [2]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [3]航天时代飞鸿技术有限公司,北京100094 [4]中国农业大学水利与土木工程学院,北京100083

出　　处：《水力发电学报》2023年第3期141-152,共12页Journal of Hydroelectric Engineering

基　　金：清华大学水沙科学与水利水电工程国家重点实验室开放基金项目(sklhse-2022-C-03);国家自然科学基金(52209161);中央高校基本科研业务专项资金项目(2021MS042)。

摘　　要：为了研究堆石混凝土早龄期温度的非均匀时空分布特征,本文开发了考虑自密实混凝土分层填充和离散堆石颗粒体的非均质材料温度仿真方法,并结合石坝河水库的原型监测试验开展温度变化规律研究。结果发现,初始状态浇筑填充期的非均匀入仓温度,几个小时内即可完成混合均匀过程;早龄期第二阶段为堆石体与自密实混凝土的共同温升过程,约2~3天时间,而堆石辅助吸热的温升幅度与速率低于自密实混凝土的;之后堆石混凝土整体温度趋向均匀稳定,并缓慢下降。浇筑仓不同区域的堆石率略有差异,堆石率越高的地方平均温度越低;靠近钢模板的上游防渗层与下游三角区域几乎无堆石,夏季施工时温度峰值及温度梯度较高,要引起工程重视;上仓混凝土浇筑对下层仓浅表层的“二次温升”影响约6℃,深度1.0 m以下的区域影响很小;若仓面浇筑期短,采用均质堆石混凝土模拟施工期温度是高效的替代方案,但要合理选择等效入仓温度和等效绝热温升值。To study the non-uniform spatial and temporal distributions of the early-age temperature of rock-filled concrete(RFC),this study develops a numerical method for simulating heterogeneous RFC,considering the layered filling process of self-compacting concrete(SCC)and discrete rockfill particles.We examine variations of RFC temperature by combining with the data from the prototype experiment of temperature in the Shibahe reservoir.The results show that in the initial stage of SCC pouring and filling,the mixing of concrete with non-uniform placement temperature is completed in several hours.The second stage of the RFC early age,or a synchronous temperature rise process of the rockfill and SCC,takes roughly 2-3 days,during which the rockfill promotes hydration heat absorption with a rockfill temperature rise and a rising rate both lower than those of SCC.After that,the overall RFC temperature tends to be stable and homogeneous with a trend of decreasing slowly.On a lift surface,the rockfill ratio of its different areas may be slightly different,and a higher value occurs in the area with lower average temperature.In summer construction,attention should be paid to the areas near steel formworks,because they feature a high temperature peak and steep temperature gradients due to few rocks in their upstream seepage-prevention layers or downstream triangle areas.Concrete pouring imposes a significant influence on the shallow surface layer of a lower bin,causing a secondary temperature rise of about 6℃and little effect on the layer below the 1.0 m depth.For a lift surface with a short SCC pouring period,an efficient alternative is to use a homogeneous RFC model to simulate the temperature during the construction period,but it should select reasonably an equivalent placement temperature and an equivalent adiabatic temperature rise.

关 键 词：堆石混凝土 温度仿真 非均质混凝土 分层填充过程 早龄期温度特性 

分 类 号：TV431[水利工程—水工结构工程]