Infrastructure and transportation facilities have increased rapidly over the years. The progress has been accompanied by an increasing number of vehicle collisions with structures. This type of collision might lead to the damage, and often, collapse of the structure. In reinforced concrete (RC) structures, columns are usually the most vulnerable members exposed to collisions. However, the existing design guidelines and provisions for protection of these members against collision of vehicles are not adequate. In particular, the desired behavior and the associated performance levels of a structure during a vehicle collision are not defined. Therefore, there is need to assess the vulnerability of structures against such collisions. This research aims to develop a framework for the performance-based analysis and design of RC columns subject to vehicle impact. It helps mitigate maximum damage and achieve an economical design. The current research takes into account performance-based analysis and design as opposed to only collapse prevention design. The performance level is tied to the impact levels to estimate the reliability of the RC column for the desired performance objectives. The performance-based probabilistic models for estimating shear resistance of RC column and shear demand on RC column are developed. The reliability of the RC column subject for selected performance levels is evaluated. The performance levels are tied to impact demand and load and resistance factors are proposed to achieve desired performance objectives of the RC column subject to vehicle collision.

To assess the losses associated with future earthquakes, seismic vulnerability functions are commonly used to correlate the damage or loss of a structure to the level of seismic intensity. A common procedure in seismic vulnerability assessment is to estimate the seismic fragility, which is defined as the conditional probability that a structure fails to meet the specific performance level for given level of seismic intensity. This dissertation proposes a methodology to estimate the fragility of corroded reinforced concrete (RC) bridges with two-column bents subject to seismic excitation. Seismic fragility functions are first developed for the RC bridges with two-column bents. All available information from science/engineering laws, numerical analysis, laboratory experiments, and field measurements has been used to construct the proper form of the fragility functions. The fragility functions are formulated, at the individual column, bent, and bridge levels, in terms of the spectral acceleration and the ratio between the peak ground velocity and the peak ground acceleration. The developed fragility functions properly account for the prevailing uncertainties in fragility estimation. The probabilistic capacity and demand models are then combined with the probabilistic models for chloride-induced corrosion and the time-dependent corrosion rate. The fragility estimates for corroded RC bridges incorporates the uncertainties in the parameters of capacity and demand models, and the inexactness (or model error) in modeling the material deterioration, structural capacity, and seismic demands. The proposed methodology is illustrated by developing the fragility functions for an example RC bridge with 11 two-column bents representing current construction in California. The developed fragility functions provide valuable information to allocate and spend available funds for the design, maintenance, and retrofitting of structures and networks. This study regarding the vulnerability of corroding RC bridges will be of direct value to those making decisions about the condition assessment, residual life, and the ability of lifeline structures to withstand future seismic demands.

Le but de cette thèse est de proposer des méthodes de gestion des approvisionnements adaptées à des contextes particuliers afin de minimiser les coûts logistiques engendrés dans un réseau logistique multi produits, multi niveaux confronté à une demande probabiliste. Au cours de cette thèse, nous nous sommes attachés à : - Proposer des méthodes de gestion des stocks et du transport pour des familles de produits dans différents contextes : - Une première politique de réapprovisionnement est proposée pour une famille de produits caractérisée par une demande aléatoire et répétitive. Cette politique est définie par un niveau de commande et par un niveau de ré-complètement de stock pour chaque produit et une période de réapprovisionnement. Dès qu’un produit atteint le niveau de commande, un réapprovisionnement de tous les produits de la famille est déclenché. - Une deuxième politique de réapprovisionnement est proposée pour une famille de produits caractérisée par une demande très aléatoire et ponctuelle. Cette politique est basée sur les ruptures de stock. A chaque rupture d’un produit présent dans le stock il y a déclenchement d’un réapprovisionnement de tous les produits de la famille. - Proposer une méthode de classification multicritères afin de constituer des groupes de produits relevant d’une politique donnée, chaque classe ou famille regroupant des produits réagissant identiquement. Cette classification des produits en familles homogènes permet d’identifier les caractéristiques déterminantes dans le choix des méthodes de gestion de stock et de transport. - Analyser et comparer les performances de ces deux politiques d’approvisionnement par rapport à des politiques de référence, ainsi que leur sensibilité au regard de quelques paramètres discriminants : variabilité de la demande ; coût des produits ; coût des commandes urgentes… / The aim of this work is to propose methods of inventory management tailored to specific contexts in order to minimize logistics costs incurred in a logistics network multi-product, multi-level faces a probabilistic demand. In my research work, we have focused on the following scientific key-issues: - The proposal of methods of inventory and transportation management for products families in different contexts. The first one is defined to solve the problems identified in a product family characterized by a variable and repetitive demand. This policy is defined by an ordering and a replenishment level for each product and a periodic review. As soon as a product reaches the ordering level, replenishment of the same family products is triggered. • The second one is dedicated to a product family which is characterized by a very punctual and variable demand. This policy is based on inventory shortages. Each shortage of a product in store triggers replenishment of all products of the same family. - The proposal of a multi-criteria classification method in order to select the suitable inventory management method according to specificities of the product and the demand - The analysis and performance comparison of the two procurement policies proposed with standard policies, and their sensitivity with respect to some parameters discriminating: demand variability, cost of products, cost of rush orders.

There has been increasing interest in evaluating the performance of existing reinforced concrete (RC) bridges just after natural disasters or man-made events especially when the defects are invisible, or in quantifying the improvement after rehabilitations. In order to obtain an accurate assessment of the reliability of a RC bridge, it is critical to incorporate information about its current structural properties, which reflects the possible aging and deterioration. This dissertation proposes to develop an adaptive reliability analysis of RC bridges incorporating the damage detection information obtained from nondestructive testing (NDT). In this study, seismic fragility is used to describe the reliability of a structure withstanding future seismic demand. It is defined as the conditional probability that a seismic demand quantity attains or exceeds a specified capacity level for given values of earthquake intensity. The dissertation first develops a probabilistic capacity model for RC columns and the capacity model can be used when the flexural stiffness decays nonuniformly over a column height. Then, a general methodology to construct probabilistic seismic demand models for RC highway bridges with one single-column bent is presented. Next, a combination of global and local NDT methods is proposed to identify in-place structural properties. The global NDT uses the dynamic responses of a structure to assess its global/equivalent structural properties and detect potential damage locations. The local NDT uses local measurements to identify the local characteristics of the structure. Measurement and modeling errors are considered in the application of the NDT methods and the analysis of the NDT data. Then, the information obtained from NDT is used in the probabilistic capacity and demand models to estimate the seismic fragility of the bridge. As an illustration, the proposed probabilistic framework is applied to a reinforced concrete bridge with a one-column bent. The result of the illustration shows that the proposed framework can successfully provide the up-to-date structural properties and accurate fragility estimates.