基于等效时间的混凝土水管冷却等效热传导

采用等效时间成熟函数反映不同温度历程下混凝土的水化反应状态，对考虑混凝土水化度的水管冷却等效热传导进行了研究，推导了基于等效时间的混凝土水管冷却等效热传导有阴无计算公式，研制了相关的有限元程序．在计算有热源水管冷却问题的混凝土平均温度时，需要存储各高斯点、各增量步等效时间增量．以获得时间增量区间对应的等效时间增量区间，然后计算考虑混凝土水化度时，该时间区间内的水化热温升增毓．针对采取骨料预冷和通水冷却等温控措施的某实际混凝土工程，分析在高温季节浇筑的混凝土块的温度和徐变应力，结果表明温度变化范围在12－27℃，考虑混凝土水化度时计算的浇筑块温度最大增高1.022℃，但徐变应力差民较小。

Study on equivalent heat conduct of concrete using pipe cooling and equivalent time

The maturity function of equivalent time was used to describe the status of cement hydration process under different temperature histories.Taking into account degree of hydration,investigations were made on equivalent heat conduct of concrete by pipe cooling.The finite element formulation was proposed for heat conduct of pipe cooling associated with equivalent time,and the finite element codes were developed.When the concrete′s average temperature with heat source and pipe cooling was calculated,equivalent time increment of every Gauss point and every step should be stored.Equivalent time increment interval was obtained by time increment interval.Then the hydration heat increment considering concrete degree of hydration in this time increment interval was calculated.The analyses of concrete temperature and creep stress were conducted in a concrete engineering,where concrete pouring was carried out in the hot weather and measures like pre-cooling aggregate and pipe cooling were taken.It is revealed that within the temperature of 12~27 ℃,the resulting maximum increase in concrete temperature is 1.022 ℃ if considering degree of hydration,while difference in creep stress is minor.