Reliability Based Optimal Design of Laterally Loaded Pile with Limited Residual Strain Energy Capacity
Abstract—In this study, a general approach to the reliability based limit analysis of laterally loaded piles is presented. In engineering practice the uncertainties play a very important role. The aim of this study is to evaluate the lateral load capacity of free-head and fixed-head long pile when plastic limit analysis is considered. In addition to the plastic limit analysis to control the plastic behaviour of the structure, uncertain bound on the complementary strain energy of the residual forces is also applied. This bound has significant effect for the load parameter. The solution to reliability-based problems is obtained by a computer program which is governed by the reliability index calculation.
Optimal plastic limit and shake-down design of bar structures with constraints on plastic deformation
Optimal plastic design methods of discretized bar structures are presented where the objective function is the volume of the structure and the permanent deformations are controlled by introducing a constraint on the complementary strain energy of the residual internal forces. Single- and multiparameter loadings are considered and in the latter case the constraint on shakedown is also included in the optimal design procedure. Alternative formulations of the problems, where the complementary strain energy of residual forces is minimized at a given volume of the structure, are also presented. The proposed design methods are nonlinear and their solutions lead to nonlinear mathematical programming. Iterative solution techniques can also be efficiently applied. This is illustrated by an example.
D'une application pratique des indices bio-météorologiques
Abstract The purpose of the author is to determine statistically in what part of Switzerland maize could be cultivated with certain chance of rentability. The author gives first the method he used for determining the biometeorological index of four species of maize which were selected by the Swiss agronomical research stations. He has considered two possibilities for the growing period: ( a ) raising-ripening (l'approche globale); ( b ) raising-flowering, flowering-ripening (l'approche fractionee). From the biometeorological index, he calculated retrospectively the ripening time of these four species in the years 1901–1965. Assuming a priori that maize should be harvested before October 15th at the latest, he calculated, for a number of meteorological stations, the relative number of years when such conditions were fulfilled. Dividing the country in regions of similar mesoclimates and sorting these stations per region, it is possible to average the maximum altitude where maize can ripen at least 7, 8, 9 and 10 times within 10 years. Finally, taking into account the exposure and ground slope, he draws maps of the theoretically possible extension area, which maps are more reliable and detailed than the ones derived from actual means.