NONLINEAR BUCKLING OF A STRUCTURE WITH RANDOM IMPERFECTION AND RANDOMAXIAL-COMPRESSION BY A CONDITIONAL SIMULATION TECHNIQUE

This investigation deals with the buckling problem of a column with ra ndom geometric imperfection, resting on a nonlinear elastic foundation . In contrast to most of the earlier studies, it is assumed that the c olumn is subjected to a random axial compression. The random initial i mperfection is expressed in terms of buckling modes with coefficients obeying the truncated normal distribution. The external load is modele d as a random variable with the extreme-value distribution. An improve d simulation technique with high computational efficiency is employed to obtain the probability of failure of the structure. Statistical ana lysis of the simulation data is proposed, and the final result is give n in the form of confidence interval, which can be used directly in en gineering design.