| Concrete slab-on-girder construction represents a significant portion of highway and secondary road bridge types. The load distribution in such bridges is a function of many important parameters related to vehicle location, bridge geometry, girder stiffness and slab thickness. For the design of new structures, the load distribution characteristics are an important consideration for proper proportioning of the superstructure components. The assumption used in the design situation, it is that the components of the bridge are new and possess no damage. In the realm of structure health monitoring; however, the objective is often the identification of damage in part of a structure. The objective of this study is to investigate the feasibility of detecting damage in steel-free bridge decks using change in load distribution as a global index.; While the changes in distribution factors and behaviour were not large, observable trends could be correlated against the degree of cracking. In addition, a three dimensional finite element model of this bridge was created, and the experimental test results were used to calibrate this finite element model in both undamaged and damaged condition. The effects of the cracking could be modeled by introducing a full depth smeared element with a rigid link for shear transfer in the crack locations. Based on the response of the experimental model, it was determined that a global load distribution matrix could be constructed for monitoring purpose which would reliably indicate the degree of cracking in the deck. (Abstract shortened by UMI.)... |
