桥梁承台大体积混凝土温度控制数值模拟研究
发布时间：2018-08-24 16:45
【摘要】：建设中的沪通长江大桥28~#主墩承台混凝土浇筑量多达4.2万m~3,需采取温度控制措施。本文结合现场条件开展数值模拟分析,确定在夏季直晒高温条件下承台混凝土的最大绝热温升、冷却水管对流换热系数等关键参数,以及承台混凝土各控制点的温度-时间曲线。计算结果表明,若使承台混凝土温度控制指标满足设计要求,则承台混凝土浇筑后2~3 d内,作为温度控制主要工程措施的冷却水(温度为25℃左右)流速应≥1.5 m/s;达到峰值温度以后流速降低为1 m/s;随时间和混凝土内部温度变化流速可继续降低;通水降温时长应≥7 d。数值模拟结果可用于指导承台大体积混凝土的施工。
[Abstract]:The concrete pouring capacity of the bearing cap of the main pier 28# of the Hutong Yangtze River Bridge under construction is up to 42000 mm3, so temperature control measures should be taken. In this paper, the maximum adiabatic temperature rise of cap concrete and the convection heat transfer coefficient of cooling water pipe are determined under the condition of direct drying and high temperature in summer. And the temperature-time curve of each control point of cap concrete. The calculation results show that if the temperature control index of the cap concrete meets the design requirements, the concrete of the cap can be poured within 2 ~ 3 days. The velocity of cooling water (about 25 鈩，
本文编号：2201415
[Abstract]:The concrete pouring capacity of the bearing cap of the main pier 28# of the Hutong Yangtze River Bridge under construction is up to 42000 mm3, so temperature control measures should be taken. In this paper, the maximum adiabatic temperature rise of cap concrete and the convection heat transfer coefficient of cooling water pipe are determined under the condition of direct drying and high temperature in summer. And the temperature-time curve of each control point of cap concrete. The calculation results show that if the temperature control index of the cap concrete meets the design requirements, the concrete of the cap can be poured within 2 ~ 3 days. The velocity of cooling water (about 25 鈩，
本文编号：2201415
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