Construction Numerical Simulation Analysis Of Large LNG Storage Tank Dome

In order to ensure the safety of the dome of the construction of LNG storage tank at the same time consider the temperature field of the stress variation of the LNG storage tank dome, 160,000 m3 full capacity LNG storage tank dome is selected, it is carried out by adopting ADINA software. This paper studies the LNG tank dome temperature and stress variation during concrete pouring. The contents of the dissertation are as follows.Firstly, using ADINA infinite element software, a three-dimensional finite element model of LNG tank dome is established, applying TMC module of the ADINA software, considering the thermal structure interaction under the LNG storage tank dome temperature fields, and through comparative analysis and on-site temperature monitoring data, we have been obtained the temperature field of concrete hydration heat effect. The results show that: The plate temperature is close to the temperature of the concrete, first, the temperature of plate and concrete increase and then downward during concrete construction process; and temperature changes occurred in the concrete pouring parts. The highest value of the temperature appears in 2 to 3 days after the concrete pouring, the maximum is 57.2℃; the maximum temperature gradient occurs in 30 to 60 hours.Secondly, hoop stress and radial stress changes of the LNG storage tank dome plate have been studied. Results suggest that: the maximum hoop stress occurs in 30 to 60 hours. The maximum stress appears basically near the highest temperature. With the temperature field, the hoop stress curve shows the trend of first increase and then decrease. First, the radial stress increases and then decreases with the pouring of concrete, the radial stress reaches the maximum value about 30-50 hours. Through the on-site monitoring stress data and the ADINA finite element simulation values were compared, it is found that they have roughly same variations. Some simulation value and the monitoring value is quite different, which is caused by the technology limited of finite element simulation and simplified of finite element.Using a different ambient temperature and convective heat transfer coefficient for the finite element analysis, this paper, we consider the temperature field distribution of the LNG storage tank dome of 15℃, 10℃and 5℃ three ambient temperature. The analysis shows that, with the ambient temperature, the temperature of concrete surface and concrete internal has increased. The lower ambient temperature, the greater temperature difference will be generated between concrete surface and concrete centre. The greater the convective heat transfer coefficient, the faster the cooling rate of the concrete surface, the more the heat to the outside under the same conditions, the greater the temperature difference between inside and outside of the concrete.