Abstract：To investigate the evolution of hydration heat in concrete at early age, temperature fields of a box girder segment were measured by 479 thermocouples. Delaunay triangulation method was employed to establish a thermometry matrix, which made it possible to get accurate temperature fields in the process of hydration heat in box girder, and then the characteristic of temperature distribution was analyzed. The results show that the hydration temperature displays a symmetrical distribution across the vertical center axis of box girder segment. The maximum value of the hydration temperature is located in the box-girder web with a value of 64.8℃. The ratio of maximum hydration heat of tops, bottom flanges and webs of box girder is 1∶1.1∶1.4. The maximum hydration heat occurs within 11 hours after concrete casting in bottom flange, while it is 12 hours for the web and 13 hours for the top flange of box girder. The temperature variation in the thickness direction of plate follows an expression of Gaussian function, while the temperature variations in the width direction of top and bottom flanges follow a binomial expression of Gaussian function. In addition, the temperatures mainly keep in constant in height direction of box girder’s web. Groups of detailed temperature values are also provided during box girder’s hydration heat period, which can be referred in the measurement experiment of hydration temperature of concrete box girder. This work can also provide reference for the temperature control and design of box girder at the early age after concrete casting.
张 宁 周 鑫 刘永健 刘 江. 基于点阵式测量的混凝土箱梁水化热温度场原位试验[J]. 土木工程学报, 2019, 52(3): 76-86.
Zhang Ning Zhou Xin Liu Yongjian Liu Jiang. In-situ test on hydration heat temperature of box girder based on array measurement. 土木工程学报, 2019, 52(3): 76-86.
