The estimation of extreme load effects caused by vehicles is of critical importance in the evaluation and design of bridge structures. Two methods for estimating extreme load effects over the service life of bridges are commonly cited in literature: (1) the use of a fitted probability distribution based on statistical data to extrapolate the extreme load effects on a probability plot, or (2) the application of Monte Carlo simulation to generate representative truck data over a bridge’s lifespan such that maximum load effect values can then be determined directly. In this paper, results obtained using the two aforementioned methods are presented including their advantages and disadvantages in the context of the analysis of rural bridges in Saskatchewan. For this purpose, estimated load effects are based on truck data recorded over a period of one year at several weigh-in-motion (WIM) stations located on Saskatchewan highways. The conducted analyses are based on a typical bridge type common to rural Saskatchewan. It was found that the Monte Carlo simulation approach resulted in more reliable extreme load effect estimations, along with providing other information that is of value in the development of new truck loading models
