RELIABILITY ANALYSIS OF SHEARWALL STRUCTURE WITH SOIL-STRUCTURE INTERACTION (RANDOM VIBRATION, RESISTANCE, FAILURE PROBABILITY, GROUND EXCITATION)

The Reliability assessment of a site-dependent structural system under seismic environment is studied in this report.; The stiffness parameters of the system (soil as well as structure) are considered as random variable. The random distribution of modal frequencies are obtained. A new response spectral density function is defined which include the effect of randomness of the model frequencies.; A stationary random process is used to simulate the seismic excitation load along with the random operational loads.; The random vibration analysis in frequency domain is used to obtain the statistical properties of the dynamic response of structure to a stochastic ground excitation.; The limit resisting boundaries are considered as nondeterministic due to the uncertainty associated with the characteristics of mechanical properties of materials used in the construction of structure.; The Reliability analysis is performed with consideration of random stresses and random limit resisting boundaries. The multi-integration technique is used to evaluate the failure probabilities.; A typical shear wall supporting the containment building of a hypothetical nuclear power plant located on uniform sand deposit is chosen for the numerical study.; A sensitivity analysis is performed to evaluate the influence of various parameters on the reliability of the system, such as: the effect of soil-structure interaction, stiffnesses of soil, randomness of strength of materials (concrete, steel), distribution of reinforcement in concrete members, types of design spectral densities, and different level of Safe Shut Down Earthquake acceleration and maximum possible acceleration, etc.; A computer program is developed based on the method presented in this study to perform the numerical analysis.; The finds from this research are listed as follows: (1) The design of the structures with different types of design spectra would create inconsistent reliability levels. This inconsistency will be exaggerated by the uncertainty of soil-structure interaction. (2) The randomness of strength of materials shows higher influence on outcome of reliability assessment than the randomness of the stiffness of materials used in structure and soil. (3) Different arrangement of reinforcement in a concrete member changes the probabilistic limit resisting boundaries and results in different reliability values. (4) The highest impact on reliability assessment can be attributed to the Safe Shut Down Earthquake acceleration, a(,SSE), and the Maximum possible acceleration, a(,max).