柳州三门江大桥大体积混凝土温度控制技术

Control Technology for the Temperature of Massive Concrete for Liuzhou Sanmenjiang Bridge

研究目的:通过模拟柳州三门江大桥主墩承台、墩身、索塔及主桥箱梁0#块大体积混凝土现场施工情况,以及考虑混凝土物理热学性能,仿真计算大体积混凝土内部温度及应力场。从而解决大体积混凝土在施工过程中由于内外温差过大而造成开裂的问题。以便为今后大体积混凝土施工提供借鉴。研究结论:通过对大体积混凝土温度控制技术的研究和计算分析,揭示了大体积混凝土的温度特征和变化规律,提出了大体积混凝土的温度控制标准。采用合理的混凝土配合比、适当的分层浇筑和有效的保温养护措施,可以保证主墩承台、墩身、箱梁0#块和塔柱实心段各层混凝土的内外温差控制在规定的范围内。

Research purposes： By simulating the massive concrete construction of reinforcement pile cap of main pier, pier shafts, No. 0 pylons and segments of box beams of Liuzhou Sanmenjiang Bridge, and considering the physical and thermal performances of concrete, the inner temperature and stress field of massive concrete were calculated for solving the problem that massive concrete is easy to crack during construction owing to the large difference between inside and outside temperatures of it and providing the useful reference to the future construction of massive concrete. Research conclusions：Based on the research and calculation analysis, the temperature feature and change regularity of massive concrete were revealed and the standard for controlling temperature of massive concrete was proposed. The temperature differences within the fixed range between inside and outside the reinforcement pile cap of main pier, pier shafts, No. 0 pylons and segments of box beams can be guaranteed by adopting the corresponding temperature control measures, such as adopting the reasonable concrete matching ratio, proper pouting by layer and effective temperature maintenance.