Parameter Estimation of Structures from Static Strain Measurements. I: Formulation

A method for structural parameter identification utilizing elemental strain me~surements is pre­ sented. By using a subset of applied static forces and a subset o~ mea.sured su:ains, element stiffness parameters of all or a portion of a finite element model of the structure are Identified. This method preser:ves the structural connectivity and determines changes in cross-sectional properties at the el~ment level, mcludmg large. changes or element failures for stable structures. Strain measurements do not require a frame of reference; this ~akes them superior to static displacement measurements. Strain measurements are also more accurate than. ordl~ary displacement measurements and can easily be used on bridges, buildings, and spac~ structures. The Identified cross-sectional element properties can be used for damage assessment and load ratmg of structures. Two nu­ merical examples, including two-dimensional (2D) truss and frame structures, are presented and the element stiffnesses are successfully and accurately evaluated.