混凝土箱梁水化热温度损伤修正耦合方法

为了防止混凝土箱梁墩顶块在施工过程中出现早期开裂与温冲现象,研究了混凝土水化热温度损伤模型,综合考虑混凝土弹性模量与边界条件的时变效应,采用线性迭代方法,建立了混凝土箱梁墩顶块水化热温度损伤修正耦合方法,计算了水化热温度损伤场随时间变化的过程,得到了水化热温度损伤时程关系曲线,分析了温度损伤时变效应规律。计算结果与实测结果对比表明:混凝土箱梁水化热温度偏差小于10%,水化热温差峰值比水化热温度峰值滞后约32h,等效应变峰值与温差峰值发生时间相同,水化热温度损伤度与等效应变成正比,时变效应规律一致,因此,此方法可行。

Updating coupling method of hydration heat temperature damage for concrete box girder

In order to prevent the earlier crack and temperature dash phenomenon of pier-on mass for concrete box girder during construction, hydration heat temperature damage model for concrete was studied, the time-dependent effect for modulus of elasticity and boundary conditions were comprehensively considered, an updating coupling method of hydration heat temperature damage for the girder was put forward by using linear iteration method, the whole damage field with the variation procedure of temperature load was computed, and the damage laws were analyzed based on the time-dependent relation curves of the field. Comparison between calculated result and measurement result shows that the deviation of the hydration heat temperatures is less than 10%, the appearing time of the difference peak value for the hydration heat temperature delays about 32 h compared with the temperature peak value, the peak values of the equivalent strain for the girder and the temperature difference appear synchronously, the hydration heat temperature damage degree is linear to the equivalent strain, their time-dependent effect laws are similar, so the model is feasible. 2 tabs, 11 figs, 15 refs.