起重机生命周期载荷谱预测及基于疲劳寿命的结构优化设计

起重机生命周期载荷谱预测及基于疲劳寿命的结构优化设计

戚其松,李成刚,董青,陈钰浩,徐航

Prediction of load spectrum for crane life cycle and structural optimal design based on fatigue life

Qisong QI,Chenggang LI,Qing DONG,Yuhao CHEN,Hang XU

表3 起重机结构在不同工况下的力学模型和内力计算公式

Table 3 Mechanical models and internal force calculation formulas of crane structure under different working conditions

工况	力学模型	计算项	计算公式	单位
工况1		跨中弯矩	$M_{z_1} = \frac{1}{8} q S^{2} + \frac{F_{m}}{2} (S - b)$	$N \cdot m m$
		跨中剪力	$F_{z_1} = - \frac{F_{m} b}{S}$	N
		跨端剪力	$F_{d_1} = \frac{q S}{2} + F_{m} (1 - \frac{b}{S})$	N
		跨中扭矩	$T_{n_1} = 2 F_{m} l_{o z}$	$N \cdot m m$
工况2		跨中弯矩	$M_{z_2} = \frac{1}{8} q S^{2} + \frac{1}{2} F_{m} (2 s_{d} + b)$	$N \cdot m m$
		跨中剪力	$F_{z_2} = - F_{m} \frac{2 s_{d} + b}{S}$	N
		跨端剪力	$F_{d_2} = \frac{q S}{2} + F_{m} (2 - \frac{2 s_{d} + b}{S})$	N
		跨端扭矩	$T_{n_2} = 2 F_{m} l_{o d}$	$N \cdot m m$
工况3		跨中弯矩	$M_{z_3} = \frac{1}{8} q S^{2} + \frac{1}{2} F_{k} (2 s_{d} + b)$	$N \cdot m m$
		跨中剪力	$F_{z_3} = - F_{k} \frac{2 s_{d} + b}{S}$	N
		跨端剪力	$F_{d_3} = \frac{q S}{2} + F_{k} (2 - \frac{2 s_{d} + b}{S})$	N
		跨中扭矩	$T_{n_3} = 2 F_{k} l_{o z}$	$N \cdot m m$
工况4		跨中弯矩	$M_{z_4} = \frac{1}{8} q S^{2} + F_{k} (s_{d} + \frac{b}{2})$	$N \cdot m m$
		跨中剪力	$F_{z_4} = - F_{k} \frac{2 s_{d} + b}{S}$	N
		跨端剪力	$F_{d_4} = \frac{q S}{2} + F_{k} \frac{2 s_{d} + b}{S}$	N
		跨端扭矩	$T_{n_4} = \frac{q S}{2} + F_{k} \frac{2 s_{d} + b}{S}$	$N \cdot m m$