针对厂房混凝土结构施工期易开裂的问题, 采用三维非稳定温度场及应力场的有限元计算方法, 对某水电站 厂房下部大体积混凝土结构的施工全过程进行数值模拟, 揭示其温度场及应力场的发展过程和分布规律, 并根据计 算结果提出切实可行的温控防裂措施。经分析发现, 在低温入仓的基础上, 采取表面保温和内部导热降温相结合的 温控防裂措施, 可有效降低混凝土早期的内外温差和后期的温降幅度, 从而提高厂房混凝土的抗裂安全性。

The concr ete st ructur e of hydro power st ation pow erhouse can easily crack dur ing t he co nstr uction per io d. In this pa2 per, three2dimensio na l finite element method w ith unsteady temperature and st ress field w as used to simulate the w hole con2 str uction pr ocess o f the under part concrete structure of a hy dr opow er st ation power ho use. The develo pment process and distr i2 bution r eg ular ity of the temper ature field and str ess field w ere o btained, and the feasible temper ature contro l and crack preven2 tion metho ds w ere proposed accor ding t o the computation results. The analy sis show ed that on t he basis o f low t em perat ur e be2 fo re concrete pouring , temperature contr ol and crack pr event ion measur es w ith surface heat pr eser vation and inter nal heat con2 duction can effectively decrease the temper ature difference betw een the internal and exter na l early2ag e concrete, and also de2 cr ease the temper ature amplit ude of later2ag e concrete, w hich can impro ve the safety ag ainst cracking of the pow erhouse con2 cr et e.

国家自然科学基金资助项目( 51109081; 51309101)