Automated reliability based design of footing foundations

Wilson H. Tang

Department of Civil and Structural Engineering, Hongkong University of Science and Technology, People’s Republic of China

B.K.Low

School of Civil and Structural Engineering, Nanyang Technological University, Singapore

Proceedings, 7^th International Conference on Structural Safety and Reliability, ICOSSAR ’97, Kyoto, Japan, Vol. 3, pp. 1837-1840, A.A. Balkema Publishers.

First order reliability method can be implemented efficiently using an optimization tool that resides in most spreadsheet software. Correlated random variables and complicated non-explicit performance functions are dealt with easily. As illustrations, design examples are given to dimension footing foundation for a desired reliability. The reliability for multiple failure modes are also evaluated, and compared with Monte Carlo simulation using spreadsheet.

Practical First-Order Reliability Computations Using Spreadsheet

B. K. Low
School of Civil and Structural Engineering, Nanyang Technological University, Singapore

K. K. Phoon
Department of Civil Engineering, National University of Singapore, Singapore

The Hasofer-Lind (1974) index and the first order reliability method (FORM) have been treated in Rackwitz and Fiessler (1978), Ditlevsen (1981), Shinozuka (1983), Ang and Tang (1984), Madsen et al. (1986), and Tichy (1993). The continuing interest in FORM is also evident in Melchers (1999), Haldar and Mahadevan (1999), Nowak and Collins (2000), for example. The potential inadequacies of FORM in some special cases have been recognized, and more refined alternatives proposed (e.g. Der Kiureghian et al.1987). On the other hand, Rackwitz (2001) noted the usefulness and accuracy of FORM in most applications; some counterexamples were summarized, their rather extreme nature and artificiality noted, but their healthy role also admitted.