中文摘要：

薄壁结构广泛应用于实际工程中,局部材料性能的变化、局部热应力等因素均影响结构的屈曲承载力。为考察局部升温对薄壁结构屈曲承载力的影响,通过激光辐照实现薄壁结构的局部快速升温。采用温度-位移耦合法进行非线性热屈曲分析,获得了激光功率密度、辐照光斑半径和薄板厚度对薄板热屈曲的影响;在此基础上采用弧长法分析轴向受压薄板结构在局部激光辐照下的整体屈曲承载力。数值结果表明：薄板结构的整体屈曲承载力随激光辐照时间的增加及辐照光斑半径的增大呈线性下降趋势,随薄板厚度的增加近似呈指数增大。

英文摘要：

Thin-walled structures have been widely used in engineering practice,and great attention has been paid to the study of local changes that occur in their material properties and thermal stress as they have a great influence on the structures＇ bearing capacity.In our study,the laser power density,irradiation spot radius and thickness of the sheet were first taken into consideration in the analysis of the thermal nonlinear buckling behavior of the thin-walled structures under local irradiation.Then,the arc-length method was applied in the investigation of the stability of the thin-walled structures under combined external loads of axial compression and laser irradiation.Our numerical results indicated that the buckling capability of the thin-walled structures decreases almost linearly with the increase of irradiation time and irradiation spot radius,but increases exponentially along with the increase of sheet thickness.