Wuhan University of Technology> Triangle Load求极值：≥0.317时：y出现在第一阶段T-≤0.317时，y出现在第二阶段T放大系数：0.20.40.50.751.01.52.0T,/T0.1250.250.371002.0B0.390.60.731.01.051.211.551.691.421.766-11
6-11 Wuhan University of Technology Triangle Load 放大系数： 求极值： 时， 出现在第二阶段 时： 出现在第一阶段 max 1 max 1 0.317 0.317 y Tt y Tt T1/T 0.125 0.2 0.25 0.371 0.4 0.5 0.75 1.0 1.5 2.0 ∞ β 0.39 0.6 0.73 1.0 1.05 1.21 1.42 1.55 1.69 1.76 2.0
Wuhan Universityof Technologyspectrum of magnification factor2包络线tr2.01.03.04.02动力系数介乎1与2之间如果升载时间很短，t<T/4，则β接近于2.0，即相当于突加荷载的情况；如果升载时间很长，t,>4T，则β接近于1.0，即相当于静荷载的情况。76-12
6-12 Wuhan University of Technology spectrum of magnification factor 0 1.0 2.0 3.0 4.0 T t r 1.4 1.2 1.0 1.6 1.8 2.0β tr P 0 动力系数介乎 1 与 2之间; 如果升载时间很短， t r<T/4，则 β接近于2.0，即相当于突加荷载的情况; 如果升载时间很长， t r> 4T，则 β接近于1.0，即相当于静荷载的情况。 包络线
Wuhani5.2 Sine-wave impulse+p(t)Universityof TechnologyPoT=t-tPhase IPhase IIForimpulsiveloadswhichcanbeexpressedbysimpleanalyticalfunctions,closedformsolutionsoftheequationsofmotioncanbeobtained.Forexample,considerthe singlehalfsinewaveimpulse shown inFig.52.Theresponsetosuchanimpulsewillbedividedintotwophasesasshown,thefirstcorrespondingtotheforcedvibrationphaseintheinterval duringwhichthe load acts and the second corresponding to the freevibration phase whichfollows.6-13
6-13 Wuhan University of Technology 5.2 Sine-wave impulse For impulsive loads which can be expressed by simple analytical functions, closed form solutions of the equations of motion can be obtained. For example, consider the single halfsinewave impulse shown in Fig. 52. The response to such an impulse will be divided into two phases as shown, the first corresponding to the forcedvibration phase in the interval during which the load acts and the second corresponding to the freevibration phase which follows