用于输电线路杆塔组立的双摇臂落地抱杆杆身抗压可靠性分析

Analysis of Compressive Reliability of Double Rocker Floor Holding Pole Used for the Tower Erection in transmission line

为了研究双摇臂落地抱杆杆身构件的抗压可靠性,考虑冲击动荷载的随机性,用冲击荷载系数乘以总质量来模拟抱杆受到的冲击动荷载,结合最大风荷载构成可变荷载施加于双摇臂落地抱杆有限元模型;采用有限元法进行分析,得到最不利工况(0°和45°)下,双摇臂落地抱杆杆身构件受到的可变荷载作用效应的分布特征和统计参数;结合实测的杆身构件几何参数统计特征,利用JC法求得双摇臂落地抱杆杆身构件0°和45°工况下的轴向抗压可靠度分别为4.746和4.742,并求得考虑可变荷载作用效应和恒定荷载作用效应比值ρ变化时的可靠度。分析结果表明,冲击动荷载会减小杆身构件的轴向抗压可靠度,随着ρ值的增大,杆身构件的轴向抗压可靠度逐渐降低。在实际工作过程中应避免可变荷载的增大和45°工况,以提高抱杆的可靠度与使用的全寿命周期,降低施工安全风险。

In order to study the compression resistance reliability of the double rocker floor holding pole,this paper considers the randomness of the impact dynamic load,uses the impact load coefficient multiplied by the total mass to simulate the impact dynamic load of the holding pole,and combines the maximum wind load to form a variable load,which is applied to the finite element model of the double rocker floor holding pole.By using the finite element analysis method,it obtains the distribution characteristics and statistical parameters of variable load effects of the components of the pole under the most unfavorable conditions of 0°and 45°.Combining with the measured statistical characteristics of the geometric parameters of the pole body members,the paper uses JC method to calculate the degrees of axial compression resistance reliability of the double rocker floor holding pole under 0°and 45°conditions,respectively are 4.746 and 4.742.Meanwhile,it obtains the reliability considering the ratio of the variable load effect and the constant load effect.The analysis results indicate that the impact dynamic load will reduce the axial compression resistance reliability of the members.With the increase of the ratio of the variable load effect and the constant load effect,the axial compression resistance reliability gradually decreases.To improve the reliability of the holding pole and the whole life cycle,the paper suggests to avoid the increase of the variable load and 45°working condition in the actual work process,and reduce the construction safety risk.