基于单向耦合多尺度多场模型的大体积混凝土开裂风险分析

The cracking risk of mass concrete based on a unidirectional coupled multi-field and multi-scale model

为有效评估大体积混凝土开裂风险,基于有限元二次开发工具,构造一种单向耦合的混凝土多尺度热-力模型,计算模型温度场,并通过现场监测数据验证温度场计算结果,获得不同时刻混凝土的水化度分布,结合配合比信息得到混凝土微观组分比;基于四尺度混凝土多尺度模型,获得早龄期混凝土的弹性模量、强度等宏观性能;基于应力-强度比评估大体积混凝土开裂风险。本研究工作可以指导工程人员针对性优化配合比及施工养护措施,降低大体积混凝土开裂风险,确保结构耐久性能。

In order to evaluate the cracking risk of mass concrete effectively,a unidirectional coupled multi-scale thermal mechanical coupling model of concrete was established based on the custom development tool of finite element software.The temperature field of the model was calculated,and the temperature field results were verified by the field monitoring data.Based on the temperature field results,the hydration degree distributions of concrete at different time were obtained.Combined with the initial mixture proportion,the component ratio of concrete at the corresponding time was obtained.Based on the four-scale multi-scale model of concrete,the macro properties of early age concrete,including elastic modulus,strength,etc.,were obtained.The cracking risk of mass concrete was evaluated based on the stress strength ratio.The research could assist the engineers to optimize the mix proportion and construction maintenance for reducing the cracking risk of mass concrete and assuring the durability of structure.