丽达
丽达的文档功能。
helpFun (“利达”)
线性隐式动态分析[U, UT UTT] =丽达(DT, XGTTω,KSI情况,UT0,寒冷的,RINF)描述线性隐式时间直接集成运动的二阶微分方程线性弹性应用系统的动态响应一般单步单解决家人(GSSSS)发表的算法X。周&株式会社Tamma(2004)是用于直接集成的一般线性或非线性单自由度结构(应用)的动态问题。最优数值耗散和色散零阶位移零阶速度算法设计根据上述期刊文章,用于这个例程。该算法包含了线性多步(LMS)方法的范围和受限于Dahlquist障碍定理(Dahlquist, 1963)。力-位移-速度关系的应用结构是线性的。这个函数是OpenSeismoMatlab软件的一部分。它可以作为独立的,不过需要注意输入参数的正确性,因为没有检查中执行这个函数。看到example_LIDA示例。m为关于如何实现这个函数的更多细节。输入参数DT(双(1 * 1))是时间步XGTT[双(1:nstep x 1)]是加速度的列向量历史激励实施的基础。 nstep is the number of time steps of the dynamic response. OMEGA [double(1 x 1)] is the eigenfrequency of the structure in rad/sec. KSI [double(1 x 1)] is the ratio of critical damping of the SDOF system. U0 [double(1 x 1)] is the initial displacement of the SDOF system. UT0 [double(1 x 1)] is the initial velocity of the SDOF system. ALGID [char(1 x :inf)] is the algorithm to be used for the time integration. It can be one of the following strings for superior optimally designed algorithms: 'generalized a-method': The generalized a-method (Chung & Hulbert, 1993) 'HHT a-method': The Hilber-Hughes-Taylor method (Hilber, Hughes & Taylor, 1977) 'WBZ': The Wood–Bossak–Zienkiewicz method (Wood, Bossak & Zienkiewicz, 1980) 'U0-V0-Opt': Optimal numerical dissipation and dispersion zero order displacement zero order velocity algorithm 'U0-V0-CA': Continuous acceleration (zero spurious root at the low frequency limit) zero order displacement zero order velocity algorithm 'U0-V0-DA': Discontinuous acceleration (zero spurious root at the high frequency limit) zero order displacement zero order velocity algorithm 'U0-V1-Opt': Optimal numerical dissipation and dispersion zero order displacement first order velocity algorithm 'U0-V1-CA': Continuous acceleration (zero spurious root at the low frequency limit) zero order displacement first order velocity algorithm 'U0-V1-DA': Discontinuous acceleration (zero spurious root at the high frequency limit) zero order displacement first order velocity algorithm 'U1-V0-Opt': Optimal numerical dissipation and dispersion first order displacement zero order velocity algorithm 'U1-V0-CA': Continuous acceleration (zero spurious root at the low frequency limit) first order displacement zero order velocity algorithm 'U1-V0-DA': Discontinuous acceleration (zero spurious root at the high frequency limit) first order displacement zero order velocity algorithm 'Newmark ACA': Newmark Average Constant Acceleration method 'Newmark LA': Newmark Linear Acceleration method 'Newmark BA': Newmark Backward Acceleration method 'Fox-Goodwin': Fox-Goodwin formula RINF [double(1 x 1)] is the minimum absolute value of the eigenvalues of the amplification matrix. For the amplification matrix see eq.(61) in Zhou & Tamma (2004). Output parameters U [double(1:nstep x 1)] is the time-history of displacement UT [double(1:nstep x 1)] is the time-history of velocity UTT [double(1:nstep x 1)] is the time-history of acceleration Example (Figure 6.6.1 in Chopra, Tn=1sec) dt=0.02; fid=fopen('elcentro.dat','r'); text=textscan(fid,'%f %f'); fclose(fid); xgtt=text{1,2}; Tn=1; omega=2*pi/Tn; ksi=0.02; u0=0; ut0=0; AlgID='U0-V0-Opt'; rinf=1; [u,ut,utt] = LIDA(dt,xgtt,omega,ksi,u0,ut0,AlgID,rinf); D=max(abs(u))/0.0254 __________________________________________________________________________ Copyright (c) 2018-2022 George Papazafeiropoulos Major, Infrastructure Engineer, Hellenic Air Force Civil Engineer, M.Sc., Ph.D. Email: gpapazafeiropoulos@yahoo.gr _________________________________________________________________________