in the current engineering practices, buildings are commonly designed for an effective lifetime of 50 years. this lifetime can increase the cost of buildings with short lifetimes and can reduce the safety level of buildings with large lifetimes. in this paper, a “service-life factor” has been defined. applying this factor into the nominal values of live, earthquake, wind, and snow loads, the ef...

[1] The concept of return period is fundamental for the design and the assessment of many engineering works. In a multivariate framework, several approaches are available to its definition, each one yielding different solutions. In this paper, we outline a theoretical framework for the calculation of return periods in a multidimensional environment, based on survival copulas and the correspondi...

climate is the most important factor which control desertification .in order to detect climate changes in desert zones, time trend analysis is applied to extreme indices in kashan station using extreme climate index software (ecis). results show significant trends in extreme indices during the past decade 1995-2004 and the pronounced warming is associated with a negative trend in cold extremes....