空心薄壁墩温度效应有限元分析

为研究不同环境下空心薄壁墩的温度效应,选取寒潮降温、辐射升温、气温升温3种工况,设定不同的温差作用时间,采用MIDAS FEA进行实体模拟,并与理论计算结果对比分析。结果表明:寒潮降温作用下,空心薄壁墩内(外)壁分布竖向和环向压(拉)应力,而辐射升温和气温升温作用下,空心薄壁墩内(外)壁分布竖向和环向拉(压)应力;空心薄壁墩上下梗肋处与中心墩身的应力分布不均匀,尤其应关注寒潮降温作用时上下梗肋处温度应力带来的不利影响。随着温差作用时间的增长,空心薄壁墩内外壁的温差和温度应力均呈增大趋势,但作用时间10 h之后增幅减小。因此,作用时间为10 h时的温差分析结果与理论计算结果较为接近。

Finite Element Analysis of Temperature Effect of Hollow Thin-walled Pier

In order to study the temperature effect of hollow thin-walled piers under different conditions,the cold tide cooling,radiation heating and temperature rising were selected as the analysis condition,and different temperature difference effect time was set.The MIDAS FEA was used to simulate the solid structure,and the results were compared with the theoretical ones.The results show that the vertical pressure (tension) stress and circular pressure (tension) stress are distributed in the inner (outer) wall of the hollow thin-walled pier under the action of the cold tide cooling,while the vertical and circumferential tension (compression) stresses are distributed in the inner (outer) wall of hollow thin-walled pier under the action of radiation heating and temperature rising.The stress distribution between the upper and lower ribs of hollow thin-walled pier and the central pier is not uniform,especially the adverse effects of temperature stress at the upper and lower ribs of hollow thin-walled pier caused by cold tide cooling should be paid attention to.The temperature difference and thermal stress of the inner and outer walls of hollow thin-walled piers increase with the increase of temperature difference effect time,but the increase decreases after 10 hours of effect time.Therefore,the results of temperature difference analysis are close to those of theoretical calculation when effect time is 10 hours.