摘要
大型LNG储罐在运行期间,外罐预应力混凝土徐变效应产生较大的拉应力,从而导致混凝土的开裂,将严重影响储罐的耐久性和安全性。以山东某大型LNG储罐外罐混凝土徐变效应为例,采用ADINA有限元软件建立了LNG储罐混凝土外罐徐变精细化有限元模型,分析了在预应力、内压、自重及混凝土徐变作用下,外罐的应力、应变及裂缝分布规律,获得了外罐罐底应力及应力增量时程曲线。研究结果表明,徐变作用使外罐第一主应力随着时间的推移不断增大,在储罐运行200 d时第一主应力超过了混凝土抗拉强度,外罐混凝土开始产生沿竖向分布的环向裂缝。该研究成果可为LNG储罐结构设计提供一定参考。
During the operation of large-scale LNG storage tanks,prestress concrete creep effect causes a great tensile stress on the external tank,which leads to concrete cracking and seriously affects the durability and safety of tanks.A prestress concrete tank of a large-scale LNG storage tank in Shandong is taken as an example,and a refined finite element model of the prestress concrete tank of LNG storage tanks is established by the finite element software ADINA,the stress,strain and cracking distribution rules of external tanks under the action of prestress,internal pressure,gravity and concrete creep,and the time travel curve of the bottom stress of external tank bottom and stress increment.The study results show that creep effect makes the first principal stress increase with the increase of time,the first principal stress exceeded the tensile strength of concrete when the tank runs 200d,and the concrete of the external tank began to produce circumferential concrete cracks along the vertical distribution.The results of the study can provide certain reference for LNG storage tank structure design.
作者
韩明一
李海鹏
李维恒
杨艳东
HAN Mingyi;LI Haipeng;LI Weiheng;YANG Yandong
出处
《油气田地面工程》
2018年第11期54-57,共4页
Oil-Gas Field Surface Engineering
基金
山东省自然科学基金"大型LNG储罐预应力混凝土超低温性能研究及其优化设计"(ZR2012EEL23)
中央高校基本科研业务费专项资金资助"大型LNG储罐球形混凝土罐顶裂缝开展分析"(15CX05004A)
关键词
LNG储罐
混凝土徐变
外罐应力
裂缝分布
有限元分析
LNG storage tanks
concrete creep
external tank stress
crack distribution
finite element analysis
