冻融作用下粉煤灰引气混凝土动弹性模量的衰减规律研究

发布时间：2018-06-26 13:07

本文选题：混凝土 + 冻融循环　；参考：《水利水电技术》2017年03期

【摘要】：针对我国西北寒旱区水工混凝土结构长期遭受冻融循环作用导致耐久性能衰减的问题,以研究冻融作用下混凝土力学性能变化规律为目标,依据实际工程,采用室内加速试验与理论分析方法,以试块相对动弹性模量为评价指标,研究了混凝土水胶比、粉煤灰掺量、引气剂掺量及冻融循环次数对混凝土耐久性衰减的影响规律,采用回归分析法建立了混凝土动弹性模量损失的衰减模型,并基于该模型构建冻融循环作用下混凝土的寿命预测模型。结果表明:以初始动弹性模量的60%(2.424×10~4MPa)为破坏条件,甘肃省景泰川提灌工程二期总干渠5#渡槽的混凝土能经历1 502次快速冻融循环,渡槽材料耐久性安全运行年限为153年。研究成果为冻融环境下混凝土结构的寿命预测提供了参考和依据。
[Abstract]:In view of the long-term deterioration of the durability of hydraulic concrete structures in the cold and dry areas of Northwest China, in order to study the change law of mechanical properties of concrete under freezing thawing, the relative dynamic modulus of elasticity of the test block is studied by the method of indoor accelerated test and theoretical analysis. The effect of concrete water to glue ratio, fly ash content, air entraining agent content and freezing thawing cycle times on concrete durability attenuation, the loss model of concrete dynamic elastic modulus is established by regression analysis method, and based on this model, the life prediction model of concrete under freezing and thawing cycle is constructed. The results show that the initial dynamic elasticity is based on the model. The 60% (2.424 x 10~4MPa) modulus of modulus is a failure condition. The concrete of the 5# aqueduct of the two phase of the main channel of the Jing Taichuan irrigation project in Gansu province can undergo 1502 rapid freezing and thawing cycles, and the durability of the aqueduct material has been operated for 153 years. The research results provide reference and basis for the life prediction of concrete structures under the freezing and thawing environment.
【作者单位】：华北水利水电大学;水资源高效利用与保障工程河南省协同创新中心;
【基金】：国家自然科学基金资助项目(51279064;51579102) 河南省教育厅科技创新人才支持计划(14HASTIT047);河南省教育厅科技创新团队支持计划(14IRTSTHN028) 2017年河南省杰出人才支持计划华北水利水电大学研究生教育创新计划资助项目(YK2015-01)
【分类号】：TV431

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