7.12. sdfResponse command

sdfResponse(m, zeta, k, Fy, alpha, dtF, filename, dt[, uresidual, umaxprev])

It is a command that computes bilinear single degree of freedom response in C++, and is much quicker than using the OpenSees model builder. The command implements Newmark’s method with an inner Newton loop.

m (float)


zeta (float)

damping ratio

k (float)


Fy (float)

yielding strength

alpha (float)

strain-hardening ratio

dtF (float)

time step for input data

filename (str)

input data file, one force per line

dt (float)

time step for analysis

uresidual (float)

residual displacement at the end of previous analysis (optional, default=0)

umaxprev (float)

previous displacement (optional, default=0)

The command returns a list of five response quantities.

umax (float)

maximum displacement during analysis

u (float)

displacement at end of analysis

up (float)

permanent residual displacement at end of analysis

amax (float)

maximum acceleration during analysis

tamax (float)

time when maximum accleration occurred