基于保温试验的薄壁混凝土等效放热系数反分析方法

Thermal insulation experiment-based inverse analysis method of equivalent heat-release coefficient of thin-wall concrete

【目的】采取保温措施是保证混凝土温差不超标的主要温控措施之一。其中准确的表面放热系数计算公式是获取保温参数的主要途径。【方法】基于混凝土等效放热系数计算基本公式,充分考虑风速、温度、湿度、粗糙度、黏结面积等边界影响因素,分析上述因素对保温参数的影响规律,解析计算考虑各项边界影响因素的保温参数求解关系式。同时,基于多个船闸闸室底板的温度监测数据对覆盖不同保温材料的混凝土等效放热系数进行反演分析,对比分析传统计算公式、改进后公式与实测反演结果。【结果】结果显示,提出的考虑各个边界条件影响因素的等效放热系数求解公式获取的结果与实际反演较为一致,可以应用在设计施工阶段确定不同边界条件下保温参数的精确求解,【结论】研究成果可以为混凝土温控防裂提供专业技术支撑。

[Objective]Thermal insulation measure is one of the main temperature control measures to ensure that the temperature difference does not exceed the relevant standard,while accurate calculation formula of the surface heat-release coefficient is the main path to obtain the relevant thermal insulation parameters,for which the related study is made herein.[Methods]Based on the basic formula for the calculation of the concrete equivalent heat-release coefficient,all the boundary influencing factors(wind speed,temperature,humidity,roughness,bonding area,etc.)are fully considered and the laws of their influences on the thermal insulation parameters are analyzed,and then all boundary influencing factors-considered relation formulas for solving the thermal insulation parameters are analytically calculated.Meanwhile,the equivalent heat-release coefficients of the concretes covered with different insulation materials are inversely analyzed on the basis of the temperature monitoring data of the chamber bottom slabs of several ship-locks,while the conventional calculation formula,the improved formula and the measured inversion result are comparatively analyzed.[Results]The result show that the result obtained from the all boundary influencing factorsconsidered solving formula of the equivalent heat-release coefficient proposed herein are more consistent with the actual inversions and then can be applied to determine the accurate solutions of the thermal insulation parameters under different boundary conditions during the design and construction stages.[Conclusion]The study result can provide the relevant professional technical support for temperature control and crack prevention of concrete.