大体积混凝土水化热温度特征数值分析

Numerical analysis of hydration heat temperature characteristics of massive concrete

为研究大体积混凝土水化热温度规律,防止早龄期混凝土开裂,以普立特大桥重力式锚碇散索鞍支墩基础第1层混凝土浇筑过程为例,对其水化热温度进行了连续监测.对实测混凝土水化热温度进行拟合分析,提出了基于指数函数和的形式的简化计算模型,该模型对混凝土水化热温升的拟合优度较好.利用混凝土温度有限元计算理论,结合散索鞍支墩基础所处的环境状况,建立考虑冷却管的三维有限元模型,对混凝土浇筑过程中的温度场进行模拟计算,计算结果和实测值吻合度高,并对散索鞍支墩基础在有无冷却管下的水化热温度进行了对比分析,为工程实际提供有益的参考.

To investigate hydration heat temperature rules of massive concrete and prevent concrete crack in early age,taking the process of concrete placement of first floor of gravity anchorage splay saddle pier foundation of Pu-li Extra-large bridge as an example,the hydration heat temperature was monitored continuously. Fitting analysis of the measured concrete hydration heat temperature was conducted,and a calculation model was presented based on the two terms of exponential function to show good goodness of fit for concrete hydration heat temperature rise. Using the finite element theory with consideration of environment conditions of splay saddle pier foundation,the 3-D finite element model including cooling pipe was built to calculate the temperature in the process of concrete casting. The results show that the calculation results are well consistent with the measured values. The comparison analysis on hydration heat temperature of splay saddle pier foundation with or without cooling pipe offers beneficial references for practical engineering.