章我应力
Chapter 11 Alternating Stress
卖妄应动( Alternating Stress 第十4 交变应力 (Alternating stress) D11交变应力与疲劳失效( Alternating stress and fatigue failure) §11-2交变应力的循环特征、应力幅和平 均应力( The cycle symbol, stress amplitude and mean stress for alternating stress) 11-3持久极限( Endurance limit) s11-4影响持久极限的因素 (The effective factors of endurance limit)
(Alternating Stress) 第十一章 交变应力 （Alternating stress） §11–1 交变应力与疲劳失效(Alternating stress and fatigue failure) §11–3 持久极限(Endurance limit) §11–2 交变应力的循环特征、应力幅和平 均应力(The cycle symbol,stress amplitude and mean stress for alternating stress） §11–4 影响持久极限的因素 (The effective factors of endurance limit )
卖妄应动( Alternating Stress §11-5对称循环下构件的疲劳强度计算 (Calculation of the fatigue strength of the member under symmetric cycles) §11-6持久极限曲线 (Enduring limit curve) 口§11-7不对称循环下构件的疲劳强度计算 (Calculation of the fatigue strength of the member under unsymmetric cycles) p§11-8弯扭组合交变应力的强度计算 Calculation of the strength of composit deformations
(Alternating Stress) §11–5 对称循环下构件的疲劳强度计算 (Calculation of the fatigue strength of the member under symmetric cycles) §11–6 持久极限曲线 (Enduring limit curve) §11–7 不对称循环下构件的疲劳强度计算 (Calculation of the fatigue strength of the member under unsymmetric cycles) §11–8 弯扭组合交变应力的强度计算 (Calculation of the strength of composit deformations)
卖妄应动( Alternating Stress s11-1交变应力与疲劳失效 (Alternating stress and fatigue failure) 、交变应力( Alternating stress 构件内一点处的应力随时间作周期性变化,这种应力称为交 变应力. F 6 高藤鼬 低油
(Alternating Stress) §11–1 交变应力与疲劳失效 (Alternating stress and fatigue failure) 一、交变应力（Alternating stress ) 构件内一点处的应力随时间作周期性变化,这种应力称为交 变应力. A F t s Ｏ
卖妄应动( Alternating Stress 、产生的原因( Reasons) 1.载荷做周期性变化 Load changes periodically with time) 2载荷不变,构件点的位置随时间做周期性的变化 (The point changes his location periodically with time under an unchangeable load) 例题1一简支梁在梁中间部分固接一电动机由于电动机的重力 作用产生静弯曲变形当电动机工作时,由于转子的偏心而引起离 心惯性力由于离心惯性力的垂直分量随时间作周期性的变化,梁 产生交变应力
(Alternating Stress) 二、产生的原因(Reasons) 例题1 一简支梁在梁中间部分固接一电动机,由于电动机的重力 作用产生静弯曲变形,当电动机工作时,由于转子的偏心而引起离 心惯性力.由于离心惯性力的垂直分量随时间作周期性的变化,梁 产生交变应力. 1.载荷做周期性变化 （Load changes periodically with time） 2.载荷不变,构件点的位置随时间做周期性的变化 （The point changes his location periodically with time under an unchangeable load）