寒区涵洞现浇混凝土基础水化热的影响分析

考虑相变和热量生成，导出了瞬态温度场问题的热量平衡控制微分方程，并用伽辽金法推导出了有限元计算公式。通过对青藏铁路正在修建涵洞的现浇混凝土基础水化热的影响分析，可以看出，现浇混凝土水化热在施工后半年内对涵洞周围冻土的热状况影响较大，施工后2年时仍有影响。为了减小这种影响，还计算分析了涵洞现浇混凝土基础下按2种方式铺设保温材料的冻土热状况。通过分析比较可以看出，在涵洞现浇混凝土基础下铺设保温材料可以大大减少现浇混凝土水化热对冻土热状况的影响。

Analysis of Hydration Heat Effect of Cast-in-Situ Concrete Foundations of Cold Region Culverts

Taking phase change and heat generation of cast in situ concrete into account, the governing differential equations of the problem of temperature field are presented, and the finite element formulae of this problem are obtained by Galerkin's method. From the analyses for the effect of the hydration heat of cast in situ concrete of a culvert foundation in the Qinghai Tibet Railway, it is known that the effect of the hydration heat of cast in situ concrete of culvert foundations on the rock or soil surrounding the culvert is very great within half a year, and the effect is still in existence until the second year end. To reduce this effect,the temperature fields of the two types of the insulation couses constructed under the culvert cast in situ concrete foundation are computed and analyzed.From the comparison, it can be understand that the insulation couses constructed under the culvert foundation can greatly reduce the effect of the hydration heat of cast in situ concrete of culvert foundation on the rock or soil surrounding the culvert.