苏  娟，  周美珍，  魏会东
    （海洋石油工程股份有限公司，天津300451）

[摘要] 随着国内LNG需求量的逐渐增大，对LNG混凝土储罐的高容积和安全性提出了更高的要求。借助于ANSYS有限元软件，对泄放阀火灾作用下LNG混凝土储罐罐顶端部分的高温力学性能进行了分析研究。分析中除了考虑由温度引起的材料力学性能劣化效应，还在考虑了瞬态热应变的影响。以16万m3混凝土储罐为例，给出了泄放阀火灾作用下LNG混凝土储罐罐顶和钢质穹顶的温度场和温度应变的分布情况。结果表明：泄放阀火灾作用仅在罐顶和罐壁顶端产生影响；通过温度和温度应力的分布情况，可校核火焰的位置和高度；在计算分析中确定的最高温度处应预埋热电偶，以便于实时监测混凝土的最高温度。分析结果对于提高我国大型LNG预应力混凝土储罐的设计水平具有一定的参考价值。
[关键词] 储罐；预应力混凝土；LNG；温度场；泄放阀
中图分类号：TU234.1    文献标识码：A  文章编号：1002-848X(2011) S2-0191-04

    Hight temperature analysis of LNG prestressed concrete tank for relief valve fire
    Su Juan, Zhou Meizhen, Wei Huidong
    ( Offshore Oil Engineering Co., Ltd., CNOOC, Tianjin 300451, China)

Abstract: As the demand of LNG in Cluna mcreases, there is higher requirement for the big volume and safety of LNG concrete tank. Investigation of high temperature mechanical properties of top LNG concrete tank under relief valve fire condition is done.  Both the degradation effect of material mechanical properties by temperature and transient thermal strain are considered. As an example of 160,000 cubic meters concrete tank, the distribution of temperature field and thermal strain of top LNG concrete tank and steel dome under relief valve fire condition is given. The results show that there is effect only in the top tank and the top of tank wall under relief valve fire condition.  By the distribution of temperature and thermal strain, the position and height of flame can be checked. Thermal couples should be embedded in the part of highest temperature by calculation anlyses in order to monitor the realtime temperature of the concrete. The analyses have some reference values for improving the level of desigrung large LNG prestressed concrete tank in our country.
Keywords: tank; prestressed concrete; LNG; temperature field; relief valve