船闸底板大体积混凝土时变温度场数值模拟分析

Numerical simulation and analysis of time-varying temperature field of lock floor mass concrete

针对施工期大体积混凝土温度场时变性,结合遗传算法对绝热温升参数进行反演,选取对时变温度场敏感度较大的单位质量水泥最终放热量Q0和实常数n作为反演对象并求得最优解。基于实测环境参数及反演结果,建立了ANSYS三维有限元传热模型,数值模拟结果与实测数据对比表明,水化热温度场时效模式更能准确地模拟工程实际。时变温度场与温差变化规律分析结果表明:大体积混凝土分层浇筑施工的温度峰值跟层厚与浇筑间隔等有关,且不一定位于各层中心;温度峰值历时曲线和里表温差历时曲线发展规律相似,可近似用于温控时间节点的参考。

Aiming at discussing the time-varying characteristics of massive concrete in the construction period, we use Genetic Algorithm to inverse the parameters and achieves optimal solutions of adiabatic temperature rise, which is the major impact on the adiabatic temperature rise of mass concrete, i. e., the unit mass of cement the final heat Q0 and the real constant n. Based on the actual measurement of environmental parameters and inversion results, we establish the three-dimensional finite element heat-transfer model of ANSYS . Comparing the results of numerical simulation and measured data, we know that the temperature field of hydration heat aging model can accurately simulate the engineering practice more. The results of time-varying temperature field and temperature variation show that the mass concrete layered construction peak temperature is related to the thick and pouring interval, and not necessarily occurs in the center of each layer; The development of temperature peak duration curves is similar to the temperature difference duration curve, thus it may serve as reference for the node time of temperature controlling.