Question: Use the stability model for a truck as provided in Problem to compute the mean H that you would permit for loading a truck by stacking loads vertically so that the failure (rollover) probability does not exceed 0.01 for mean values of T of 5 to 10 ft. Use lognormal probability distributions.
Problem: The stability of a vehicle, such as a truck, can be measured using a simplified static model as follows:
Stability = T/2H
where T is the nonrandom truck width (i.e., center of the right front tire to the center of the left front tire), and H is the random location of the center of gravity of the vehicle from street level. As the ratio approaches a mean limit L = 1.0, the tendency for the vehicle to roll is increased. Assuming that H and L are random variables with coefficients of variations of 0.15 and 0.1, respectively, perform parametric analysis by assessing failure (rollover) probabilities as functions of typical T (5 to 7 ft) and mean H (2 to 4 ft) values with mean L = 1.0. Assume
(a) normal and
(b) lognormal probability distributions for all the random variables.